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Jacobsen syndrome Direct access to data Summary The 11q terminal deletion disorder (also called "Jacobsen syndrome'') is a recognized pattern of malformation caused by partial chromosome 11q monosomy. Breakpoints typically arise in 11q23.3 with deletions extending to the telomere. More than 150 cases have been reported in the literature, with 110 of these being part of a single prospective study. The deletion of variable size gives rise to several phenotypes of varying severity, including multiple dysmorphic features, congenital heart defects and Paris-Trousseau thrombocytopenia. Mental retardation goes from normal to moderate. Patients with mild cognitive dysfunction have near-normal receptive language but moderately impaired expressive language function. Other common phenotypes include ophthalmologic, gastrointestinal symptoms, short stature, genitourinary problems, as well as fine and gross motor delays. Clinical management includes baseline cardiac evaluation and demonstration of the severe platelet dysfunction occurring in most cases. Although the decreased platelet count tends to resolve over time, platelet dysfunction is persistent, thus placing these patients at lifelong risk for bleeding. Studies of 11q deletion breakpoints reveal an interesting etiology; a folate-sensitive fragile site was shown to cause the deletions found in some patients, and breakpoints generally appear to cluster with CCG-trinucleotide repeats. *Authors: Drs P. Grossfeld and C. Jones (July 2003)*. Update : 15/04/2007

Orphanet database access

Orphanet database access

Jacobsen syndrome Direct access to data Summary The 11q terminal deletion disorder (also called "Jacobsen syndrome'') is a recognized pattern of malformation caused by partial chromosome 11q monosomy. Breakpoints typically arise in 11q23.3 with deletions extending to the telomere. More than 150 cases have been reported in the literature, with 110 of these being part of a single prospective study. The deletion of variable size gives rise to several phenotypes of varying severity, including multiple dysmorphic features, congenital heart defects and Paris-Trousseau thrombocytopenia. Mental retardation goes from normal to moderate. Patients with mild cognitive dysfunction have near-normal receptive language but moderately impaired expressive language function. Other common phenotypes include ophthalmologic, gastrointestinal symptoms, short stature, genitourinary problems, as well as fine and gross motor delays. Clinical management includes baseline cardiac evaluation and demonstration of the severe platelet dysfunction occurring in most cases. Although the decreased platelet count tends to resolve over time, platelet dysfunction is persistent, thus placing these patients at lifelong risk for bleeding. Studies of 11q deletion breakpoints reveal an interesting etiology; a folate-sensitive fragile site was shown to cause the deletions found in some patients, and breakpoints generally appear to cluster with CCG-trinucleotide repeats. *Authors: Drs P. Grossfeld and C. Jones (July 2003)*. Update : 22/04/2007

Orphanet database access

Orphanet database access

Jacobsen syndrome Direct access to data Summary The 11q terminal deletion disorder (also called "Jacobsen syndrome'') is a recognized pattern of malformation caused by partial chromosome 11q monosomy. Breakpoints typically arise in 11q23.3 with deletions extending to the telomere. More than 150 cases have been reported in the literature, with 110 of these being part of a single prospective study. The deletion of variable size gives rise to several phenotypes of varying severity, including multiple dysmorphic features, congenital heart defects and Paris-Trousseau thrombocytopenia. Mental retardation goes from normal to moderate. Patients with mild cognitive dysfunction have near-normal receptive language but moderately impaired expressive language function. Other common phenotypes include ophthalmologic, gastrointestinal symptoms, short stature, genitourinary problems, as well as fine and gross motor delays. Clinical management includes baseline cardiac evaluation and demonstration of the severe platelet dysfunction occurring in most cases. Although the decreased platelet count tends to resolve over time, platelet dysfunction is persistent, thus placing these patients at lifelong risk for bleeding. Studies of 11q deletion breakpoints reveal an interesting etiology; a folate-sensitive fragile site was shown to cause the deletions found in some patients, and breakpoints generally appear to cluster with CCG-trinucleotide repeats. *Authors: Drs P. Grossfeld and C. Jones (July 2003)*. Update : 29/04/2007

Orphanet database access

Orphanet database access

Jacobsen syndrome Direct access to data Summary The 11q terminal deletion disorder (also called "Jacobsen syndrome'') is a recognized pattern of malformation caused by partial chromosome 11q monosomy. Breakpoints typically arise in 11q23.3 with deletions extending to the telomere. More than 150 cases have been reported in the literature, with 110 of these being part of a single prospective study. The deletion of variable size gives rise to several phenotypes of varying severity, including multiple dysmorphic features, congenital heart defects and Paris-Trousseau thrombocytopenia. Mental retardation goes from normal to moderate. Patients with mild cognitive dysfunction have near-normal receptive language but moderately impaired expressive language function. Other common phenotypes include ophthalmologic, gastrointestinal symptoms, short stature, genitourinary problems, as well as fine and gross motor delays. Clinical management includes baseline cardiac evaluation and demonstration of the severe platelet dysfunction occurring in most cases. Although the decreased platelet count tends to resolve over time, platelet dysfunction is persistent, thus placing these patients at lifelong risk for bleeding. Studies of 11q deletion breakpoints reveal an interesting etiology; a folate-sensitive fragile site was shown to cause the deletions found in some patients, and breakpoints generally appear to cluster with CCG-trinucleotide repeats. *Authors: Drs P. Grossfeld and C. Jones (July 2003)*. Update : 06/05/2007

Orphanet database access

Orphanet database access

Jacobsen syndrome Direct access to data Summary The 11q terminal deletion disorder (also called "Jacobsen syndrome'') is a recognized pattern of malformation caused by partial chromosome 11q monosomy. Breakpoints typically arise in 11q23.3 with deletions extending to the telomere. More than 150 cases have been reported in the literature, with 110 of these being part of a single prospective study. The deletion of variable size gives rise to several phenotypes of varying severity, including multiple dysmorphic features, congenital heart defects and Paris-Trousseau thrombocytopenia. Mental retardation goes from normal to moderate. Patients with mild cognitive dysfunction have near-normal receptive language but moderately impaired expressive language function. Other common phenotypes include ophthalmologic, gastrointestinal symptoms, short stature, genitourinary problems, as well as fine and gross motor delays. Clinical management includes baseline cardiac evaluation and demonstration of the severe platelet dysfunction occurring in most cases. Although the decreased platelet count tends to resolve over time, platelet dysfunction is persistent, thus placing these patients at lifelong risk for bleeding. Studies of 11q deletion breakpoints reveal an interesting etiology; a folate-sensitive fragile site was shown to cause the deletions found in some patients, and breakpoints generally appear to cluster with CCG-trinucleotide repeats. *Authors: Drs P. Grossfeld and C. Jones (July 2003)*. Update : 13/05/2007

Orphanet database access

Orphanet database access

Jacobsen syndrome Direct access to data Summary The 11q terminal deletion disorder (also called "Jacobsen syndrome'') is a recognized pattern of malformation caused by partial chromosome 11q monosomy. Breakpoints typically arise in 11q23.3 with deletions extending to the telomere. More than 150 cases have been reported in the literature, with 110 of these being part of a single prospective study. The deletion of variable size gives rise to several phenotypes of varying severity, including multiple dysmorphic features, congenital heart defects and Paris-Trousseau thrombocytopenia. Mental retardation goes from normal to moderate. Patients with mild cognitive dysfunction have near-normal receptive language but moderately impaired expressive language function. Other common phenotypes include ophthalmologic, gastrointestinal symptoms, short stature, genitourinary problems, as well as fine and gross motor delays. Clinical management includes baseline cardiac evaluation and demonstration of the severe platelet dysfunction occurring in most cases. Although the decreased platelet count tends to resolve over time, platelet dysfunction is persistent, thus placing these patients at lifelong risk for bleeding. Studies of 11q deletion breakpoints reveal an interesting etiology; a folate-sensitive fragile site was shown to cause the deletions found in some patients, and breakpoints generally appear to cluster with CCG-trinucleotide repeats. *Authors: Drs P. Grossfeld and C. Jones (July 2003)*. Update : 20/05/2007

Orphanet database access

Orphanet database access

Jacobsen syndrome Direct access to data Summary The 11q terminal deletion disorder (also called "Jacobsen syndrome'') is a recognized pattern of malformation caused by partial chromosome 11q monosomy. Breakpoints typically arise in 11q23.3 with deletions extending to the telomere. More than 150 cases have been reported in the literature, with 110 of these being part of a single prospective study. The deletion of variable size gives rise to several phenotypes of varying severity, including multiple dysmorphic features, congenital heart defects and Paris-Trousseau thrombocytopenia. Mental retardation goes from normal to moderate. Patients with mild cognitive dysfunction have near-normal receptive language but moderately impaired expressive language function. Other common phenotypes include ophthalmologic, gastrointestinal symptoms, short stature, genitourinary problems, as well as fine and gross motor delays. Clinical management includes baseline cardiac evaluation and demonstration of the severe platelet dysfunction occurring in most cases. Although the decreased platelet count tends to resolve over time, platelet dysfunction is persistent, thus placing these patients at lifelong risk for bleeding. Studies of 11q deletion breakpoints reveal an interesting etiology; a folate-sensitive fragile site was shown to cause the deletions found in some patients, and breakpoints generally appear to cluster with CCG-trinucleotide repeats. *Authors: Drs P. Grossfeld and C. Jones (July 2003)*. Update : 27/05/2007

Orphanet database access

Orphanet database access

Jacobsen syndrome Direct access to data Summary The 11q terminal deletion disorder (also called "Jacobsen syndrome'') is a recognized pattern of malformation caused by partial chromosome 11q monosomy. Breakpoints typically arise in 11q23.3 with deletions extending to the telomere. More than 150 cases have been reported in the literature, with 110 of these being part of a single prospective study. The deletion of variable size gives rise to several phenotypes of varying severity, including multiple dysmorphic features, congenital heart defects and Paris-Trousseau thrombocytopenia. Mental retardation goes from normal to moderate. Patients with mild cognitive dysfunction have near-normal receptive language but moderately impaired expressive language function. Other common phenotypes include ophthalmologic, gastrointestinal symptoms, short stature, genitourinary problems, as well as fine and gross motor delays. Clinical management includes baseline cardiac evaluation and demonstration of the severe platelet dysfunction occurring in most cases. Although the decreased platelet count tends to resolve over time, platelet dysfunction is persistent, thus placing these patients at lifelong risk for bleeding. Studies of 11q deletion breakpoints reveal an interesting etiology; a folate-sensitive fragile site was shown to cause the deletions found in some patients, and breakpoints generally appear to cluster with CCG-trinucleotide repeats. *Authors: Drs P. Grossfeld and C. Jones (July 2003)*. Update : 03/06/2007

Orphanet database access

Orphanet database access

Jacobsen syndrome Direct access to data Summary The 11q terminal deletion disorder (also called "Jacobsen syndrome'') is a recognized pattern of malformation caused by partial chromosome 11q monosomy. Breakpoints typically arise in 11q23.3 with deletions extending to the telomere. More than 150 cases have been reported in the literature, with 110 of these being part of a single prospective study. The deletion of variable size gives rise to several phenotypes of varying severity, including multiple dysmorphic features, congenital heart defects and Paris-Trousseau thrombocytopenia (see this term). Mental retardation goes from normal to moderate. Patients with mild cognitive dysfunction have near-normal receptive language but moderately impaired expressive language function. Other common phenotypes include ophthalmologic, gastrointestinal symptoms, short stature, genitourinary problems, as well as fine and gross motor delays. Clinical management includes baseline cardiac evaluation and demonstration of the severe platelet dysfunction occurring in most cases. Although the decreased platelet count tends to resolve over time, platelet dysfunction is persistent, thus placing these patients at lifelong risk for bleeding. Studies of 11q deletion breakpoints reveal an interesting etiology; a folate-sensitive fragile site was shown to cause the deletions found in some patients, and breakpoints generally appear to cluster with CCG-trinucleotide repeats. *Authors: Drs P. Grossfeld and C. Jones (July 2003)*. Update : 10/06/2007

Orphanet database access

Orphanet database access

Jacobsen syndrome Direct access to data Summary The 11q terminal deletion disorder (also called "Jacobsen syndrome'') is a recognized pattern of malformation caused by partial chromosome 11q monosomy. Breakpoints typically arise in 11q23.3 with deletions extending to the telomere. More than 150 cases have been reported in the literature, with 110 of these being part of a single prospective study. The deletion of variable size gives rise to several phenotypes of varying severity, including multiple dysmorphic features, congenital heart defects and Paris-Trousseau thrombocytopenia (see this term). Mental retardation goes from normal to moderate. Patients with mild cognitive dysfunction have near-normal receptive language but moderately impaired expressive language function. Other common phenotypes include ophthalmologic, gastrointestinal symptoms, short stature, genitourinary problems, as well as fine and gross motor delays. Clinical management includes baseline cardiac evaluation and demonstration of the severe platelet dysfunction occurring in most cases. Although the decreased platelet count tends to resolve over time, platelet dysfunction is persistent, thus placing these patients at lifelong risk for bleeding. Studies of 11q deletion breakpoints reveal an interesting etiology; a folate-sensitive fragile site was shown to cause the deletions found in some patients, and breakpoints generally appear to cluster with CCG-trinucleotide repeats. *Authors: Drs P. Grossfeld and C. Jones (July 2003)*. Update : 17/06/2007

Orphanet database access

Orphanet database access

Jacobsen syndrome Direct access to data Summary The 11q terminal deletion disorder (also called "Jacobsen syndrome'') is a recognized pattern of malformation caused by partial chromosome 11q monosomy. Breakpoints typically arise in 11q23.3 with deletions extending to the telomere. More than 150 cases have been reported in the literature, with 110 of these being part of a single prospective study. The deletion of variable size gives rise to several phenotypes of varying severity, including multiple dysmorphic features, congenital heart defects and Paris-Trousseau thrombocytopenia (see this term). Mental retardation goes from normal to moderate. Patients with mild cognitive dysfunction have near-normal receptive language but moderately impaired expressive language function. Other common phenotypes include ophthalmologic, gastrointestinal symptoms, short stature, genitourinary problems, as well as fine and gross motor delays. Clinical management includes baseline cardiac evaluation and demonstration of the severe platelet dysfunction occurring in most cases. Although the decreased platelet count tends to resolve over time, platelet dysfunction is persistent, thus placing these patients at lifelong risk for bleeding. Studies of 11q deletion breakpoints reveal an interesting etiology; a folate-sensitive fragile site was shown to cause the deletions found in some patients, and breakpoints generally appear to cluster with CCG-trinucleotide repeats. *Authors: Drs P. Grossfeld and C. Jones (July 2003)*. Update : 24/06/2007

Orphanet database access

Orphanet database access

Jacobsen syndrome Direct access to data Summary The 11q terminal deletion disorder (also called "Jacobsen syndrome'') is a recognized pattern of malformation caused by partial chromosome 11q monosomy. Breakpoints typically arise in 11q23.3 with deletions extending to the telomere. More than 150 cases have been reported in the literature, with 110 of these being part of a single prospective study. The deletion of variable size gives rise to several phenotypes of varying severity, including multiple dysmorphic features, congenital heart defects and Paris-Trousseau thrombocytopenia (see this term). Mental retardation goes from normal to moderate. Patients with mild cognitive dysfunction have near-normal receptive language but moderately impaired expressive language function. Other common phenotypes include ophthalmologic, gastrointestinal symptoms, short stature, genitourinary problems, as well as fine and gross motor delays. Clinical management includes baseline cardiac evaluation and demonstration of the severe platelet dysfunction occurring in most cases. Although the decreased platelet count tends to resolve over time, platelet dysfunction is persistent, thus placing these patients at lifelong risk for bleeding. Studies of 11q deletion breakpoints reveal an interesting etiology; a folate-sensitive fragile site was shown to cause the deletions found in some patients, and breakpoints generally appear to cluster with CCG-trinucleotide repeats. *Authors: Drs P. Grossfeld and C. Jones (July 2003)*. Update : 01/07/2007

Orphanet database access

Orphanet database access

Jacobsen syndrome Direct access to data Summary The 11q terminal deletion disorder (also called "Jacobsen syndrome'') is a recognized pattern of malformation caused by partial chromosome 11q monosomy. Breakpoints typically arise in 11q23.3 with deletions extending to the telomere. More than 150 cases have been reported in the literature, with 110 of these being part of a single prospective study. The deletion of variable size gives rise to several phenotypes of varying severity, including multiple dysmorphic features, congenital heart defects and Paris-Trousseau thrombocytopenia (see this term). Mental retardation goes from normal to moderate. Patients with mild cognitive dysfunction have near-normal receptive language but moderately impaired expressive language function. Other common phenotypes include ophthalmologic, gastrointestinal symptoms, short stature, genitourinary problems, as well as fine and gross motor delays. Clinical management includes baseline cardiac evaluation and demonstration of the severe platelet dysfunction occurring in most cases. Although the decreased platelet count tends to resolve over time, platelet dysfunction is persistent, thus placing these patients at lifelong risk for bleeding. Studies of 11q deletion breakpoints reveal an interesting etiology; a folate-sensitive fragile site was shown to cause the deletions found in some patients, and breakpoints generally appear to cluster with CCG-trinucleotide repeats. *Authors: Drs P. Grossfeld and C. Jones (July 2003)*. Update : 08/07/2007

Orphanet database access

Orphanet database access

Jacobsen syndrome Direct access to data Summary The 11q terminal deletion disorder (also called "Jacobsen syndrome'') is a recognized pattern of malformation caused by partial chromosome 11q monosomy. Breakpoints typically arise in 11q23.3 with deletions extending to the telomere. More than 150 cases have been reported in the literature, with 110 of these being part of a single prospective study. The deletion of variable size gives rise to several phenotypes of varying severity, including multiple dysmorphic features, congenital heart defects and Paris-Trousseau thrombocytopenia (see this term). Mental retardation goes from normal to moderate. Patients with mild cognitive dysfunction have near-normal receptive language but moderately impaired expressive language function. Other common phenotypes include ophthalmologic, gastrointestinal symptoms, short stature, genitourinary problems, as well as fine and gross motor delays. Clinical management includes baseline cardiac evaluation and demonstration of the severe platelet dysfunction occurring in most cases. Although the decreased platelet count tends to resolve over time, platelet dysfunction is persistent, thus placing these patients at lifelong risk for bleeding. Studies of 11q deletion breakpoints reveal an interesting etiology; a folate-sensitive fragile site was shown to cause the deletions found in some patients, and breakpoints generally appear to cluster with CCG-trinucleotide repeats. *Authors: Drs P. Grossfeld and C. Jones (July 2003)*. Update : 15/07/2007

Orphanet database access

Orphanet database access

Jacobsen syndrome Direct access to data Summary The 11q terminal deletion disorder (also called "Jacobsen syndrome'') is a recognized pattern of malformation caused by partial chromosome 11q monosomy. Breakpoints typically arise in 11q23.3 with deletions extending to the telomere. More than 150 cases have been reported in the literature, with 110 of these being part of a single prospective study. The deletion of variable size gives rise to several phenotypes of varying severity, including multiple dysmorphic features, congenital heart defects and Paris-Trousseau thrombocytopenia (see this term). Mental retardation goes from normal to moderate. Patients with mild cognitive dysfunction have near-normal receptive language but moderately impaired expressive language function. Other common phenotypes include ophthalmologic, gastrointestinal symptoms, short stature, genitourinary problems, as well as fine and gross motor delays. Clinical management includes baseline cardiac evaluation and demonstration of the severe platelet dysfunction occurring in most cases. Although the decreased platelet count tends to resolve over time, platelet dysfunction is persistent, thus placing these patients at lifelong risk for bleeding. Studies of 11q deletion breakpoints reveal an interesting etiology; a folate-sensitive fragile site was shown to cause the deletions found in some patients, and breakpoints generally appear to cluster with CCG-trinucleotide repeats. *Authors: Drs P. Grossfeld and C. Jones (July 2003)*. Update : 22/07/2007

Orphanet database access

Orphanet database access

Jacobsen syndrome Direct access to data Summary The 11q terminal deletion disorder (also called "Jacobsen syndrome'') is a recognized pattern of malformation caused by partial chromosome 11q monosomy. Breakpoints typically arise in 11q23.3 with deletions extending to the telomere. More than 150 cases have been reported in the literature, with 110 of these being part of a single prospective study. The deletion of variable size gives rise to several phenotypes of varying severity, including multiple dysmorphic features, congenital heart defects and Paris-Trousseau thrombocytopenia (see this term). Mental retardation goes from normal to moderate. Patients with mild cognitive dysfunction have near-normal receptive language but moderately impaired expressive language function. Other common phenotypes include ophthalmologic, gastrointestinal symptoms, short stature, genitourinary problems, as well as fine and gross motor delays. Clinical management includes baseline cardiac evaluation and demonstration of the severe platelet dysfunction occurring in most cases. Although the decreased platelet count tends to resolve over time, platelet dysfunction is persistent, thus placing these patients at lifelong risk for bleeding. Studies of 11q deletion breakpoints reveal an interesting etiology; a folate-sensitive fragile site was shown to cause the deletions found in some patients, and breakpoints generally appear to cluster with CCG-trinucleotide repeats. *Authors: Drs P. Grossfeld and C. Jones (July 2003)*. Update : 29/07/2007

Orphanet database access

Orphanet database access

Jacobsen syndrome Direct access to data Summary The 11q terminal deletion disorder (also called "Jacobsen syndrome'') is a recognized pattern of malformation caused by partial chromosome 11q monosomy. Breakpoints typically arise in 11q23.3 with deletions extending to the telomere. More than 150 cases have been reported in the literature, with 110 of these being part of a single prospective study. The deletion of variable size gives rise to several phenotypes of varying severity, including multiple dysmorphic features, congenital heart defects and Paris-Trousseau thrombocytopenia (see this term). Mental retardation goes from normal to moderate. Patients with mild cognitive dysfunction have near-normal receptive language but moderately impaired expressive language function. Other common phenotypes include ophthalmologic, gastrointestinal symptoms, short stature, genitourinary problems, as well as fine and gross motor delays. Clinical management includes baseline cardiac evaluation and demonstration of the severe platelet dysfunction occurring in most cases. Although the decreased platelet count tends to resolve over time, platelet dysfunction is persistent, thus placing these patients at lifelong risk for bleeding. Studies of 11q deletion breakpoints reveal an interesting etiology; a folate-sensitive fragile site was shown to cause the deletions found in some patients, and breakpoints generally appear to cluster with CCG-trinucleotide repeats. *Authors: Drs P. Grossfeld and C. Jones (July 2003)*. Update : 05/08/2007

Orphanet database access

Orphanet database access

Jacobsen syndrome Direct access to data Summary The 11q terminal deletion disorder (also called "Jacobsen syndrome'') is a recognized pattern of malformation caused by partial chromosome 11q monosomy. Breakpoints typically arise in 11q23.3 with deletions extending to the telomere. More than 150 cases have been reported in the literature, with 110 of these being part of a single prospective study. The deletion of variable size gives rise to several phenotypes of varying severity, including multiple dysmorphic features, congenital heart defects and Paris-Trousseau thrombocytopenia (see this term). Mental retardation goes from normal to moderate. Patients with mild cognitive dysfunction have near-normal receptive language but moderately impaired expressive language function. Other common phenotypes include ophthalmologic, gastrointestinal symptoms, short stature, genitourinary problems, as well as fine and gross motor delays. Clinical management includes baseline cardiac evaluation and demonstration of the severe platelet dysfunction occurring in most cases. Although the decreased platelet count tends to resolve over time, platelet dysfunction is persistent, thus placing these patients at lifelong risk for bleeding. Studies of 11q deletion breakpoints reveal an interesting etiology; a folate-sensitive fragile site was shown to cause the deletions found in some patients, and breakpoints generally appear to cluster with CCG-trinucleotide repeats. *Authors: Drs P. Grossfeld and C. Jones (July 2003)*. Update : 12/08/2007

Orphanet database access

Orphanet database access

Jacobsen syndrome Direct access to data Summary The 11q terminal deletion disorder (also called "Jacobsen syndrome'') is a recognized pattern of malformation caused by partial chromosome 11q monosomy. Breakpoints typically arise in 11q23.3 with deletions extending to the telomere. More than 150 cases have been reported in the literature, with 110 of these being part of a single prospective study. The deletion of variable size gives rise to several phenotypes of varying severity, including multiple dysmorphic features, congenital heart defects and Paris-Trousseau thrombocytopenia (see this term). Mental retardation goes from normal to moderate. Patients with mild cognitive dysfunction have near-normal receptive language but moderately impaired expressive language function. Other common phenotypes include ophthalmologic, gastrointestinal symptoms, short stature, genitourinary problems, as well as fine and gross motor delays. Clinical management includes baseline cardiac evaluation and demonstration of the severe platelet dysfunction occurring in most cases. Although the decreased platelet count tends to resolve over time, platelet dysfunction is persistent, thus placing these patients at lifelong risk for bleeding. Studies of 11q deletion breakpoints reveal an interesting etiology; a folate-sensitive fragile site was shown to cause the deletions found in some patients, and breakpoints generally appear to cluster with CCG-trinucleotide repeats. *Authors: Drs P. Grossfeld and C. Jones (July 2003)*. Update : 19/08/2007

Orphanet database access

Orphanet database access

Jacobsen syndrome Direct access to data Summary The 11q terminal deletion disorder (also called "Jacobsen syndrome'') is a recognized pattern of malformation caused by partial chromosome 11q monosomy. Breakpoints typically arise in 11q23.3 with deletions extending to the telomere. More than 150 cases have been reported in the literature, with 110 of these being part of a single prospective study. The deletion of variable size gives rise to several phenotypes of varying severity, including multiple dysmorphic features, congenital heart defects and Paris-Trousseau thrombocytopenia (see this term). Mental retardation goes from normal to moderate. Patients with mild cognitive dysfunction have near-normal receptive language but moderately impaired expressive language function. Other common phenotypes include ophthalmologic, gastrointestinal symptoms, short stature, genitourinary problems, as well as fine and gross motor delays. Clinical management includes baseline cardiac evaluation and demonstration of the severe platelet dysfunction occurring in most cases. Although the decreased platelet count tends to resolve over time, platelet dysfunction is persistent, thus placing these patients at lifelong risk for bleeding. Studies of 11q deletion breakpoints reveal an interesting etiology; a folate-sensitive fragile site was shown to cause the deletions found in some patients, and breakpoints generally appear to cluster with CCG-trinucleotide repeats. *Authors: Drs P. Grossfeld and C. Jones (July 2003)*. Update : 26/08/2007

Orphanet database access

Orphanet database access

Jacobsen syndrome Direct access to data Summary The 11q terminal deletion disorder (also called "Jacobsen syndrome'') is a recognized pattern of malformation caused by partial chromosome 11q monosomy. Breakpoints typically arise in 11q23.3 with deletions extending to the telomere. More than 150 cases have been reported in the literature, with 110 of these being part of a single prospective study. The deletion of variable size gives rise to several phenotypes of varying severity, including multiple dysmorphic features, congenital heart defects and Paris-Trousseau thrombocytopenia (see this term). Mental retardation goes from normal to moderate. Patients with mild cognitive dysfunction have near-normal receptive language but moderately impaired expressive language function. Other common phenotypes include ophthalmologic, gastrointestinal symptoms, short stature, genitourinary problems, as well as fine and gross motor delays. Clinical management includes baseline cardiac evaluation and demonstration of the severe platelet dysfunction occurring in most cases. Although the decreased platelet count tends to resolve over time, platelet dysfunction is persistent, thus placing these patients at lifelong risk for bleeding. Studies of 11q deletion breakpoints reveal an interesting etiology; a folate-sensitive fragile site was shown to cause the deletions found in some patients, and breakpoints generally appear to cluster with CCG-trinucleotide repeats. *Authors: Drs P. Grossfeld and C. Jones (July 2003)*. Update : 02/09/2007

Orphanet database access

Orphanet database access

Jacobsen syndrome Direct access to data Summary The 11q terminal deletion disorder (also called "Jacobsen syndrome'') is a recognized pattern of malformation caused by partial chromosome 11q monosomy. Breakpoints typically arise in 11q23.3 with deletions extending to the telomere. More than 150 cases have been reported in the literature, with 110 of these being part of a single prospective study. The deletion of variable size gives rise to several phenotypes of varying severity, including multiple dysmorphic features, congenital heart defects and Paris-Trousseau thrombocytopenia (see this term). Mental retardation goes from normal to moderate. Patients with mild cognitive dysfunction have near-normal receptive language but moderately impaired expressive language function. Other common phenotypes include ophthalmologic, gastrointestinal symptoms, short stature, genitourinary problems, as well as fine and gross motor delays. Clinical management includes baseline cardiac evaluation and demonstration of the severe platelet dysfunction occurring in most cases. Although the decreased platelet count tends to resolve over time, platelet dysfunction is persistent, thus placing these patients at lifelong risk for bleeding. Studies of 11q deletion breakpoints reveal an interesting etiology; a folate-sensitive fragile site was shown to cause the deletions found in some patients, and breakpoints generally appear to cluster with CCG-trinucleotide repeats. *Authors: Drs P. Grossfeld and C. Jones (July 2003)*. Update : 09/09/2007

Orphanet database access

Orphanet database access

Jacobsen syndrome Direct access to data Summary The 11q terminal deletion disorder (also called "Jacobsen syndrome'') is a recognized pattern of malformation caused by partial chromosome 11q monosomy. Breakpoints typically arise in 11q23.3 with deletions extending to the telomere. More than 150 cases have been reported in the literature, with 110 of these being part of a single prospective study. The deletion of variable size gives rise to several phenotypes of varying severity, including multiple dysmorphic features, congenital heart defects and Paris-Trousseau thrombocytopenia (see this term). Mental retardation goes from normal to moderate. Patients with mild cognitive dysfunction have near-normal receptive language but moderately impaired expressive language function. Other common phenotypes include ophthalmologic, gastrointestinal symptoms, short stature, genitourinary problems, as well as fine and gross motor delays. Clinical management includes baseline cardiac evaluation and demonstration of the severe platelet dysfunction occurring in most cases. Although the decreased platelet count tends to resolve over time, platelet dysfunction is persistent, thus placing these patients at lifelong risk for bleeding. Studies of 11q deletion breakpoints reveal an interesting etiology; a folate-sensitive fragile site was shown to cause the deletions found in some patients, and breakpoints generally appear to cluster with CCG-trinucleotide repeats. *Authors: Drs P. Grossfeld and C. Jones (July 2003)*. Update : 16/09/2007

Orphanet database access

Orphanet database access

Jacobsen syndrome Direct access to data Summary The 11q terminal deletion disorder (also called "Jacobsen syndrome'') is a recognized pattern of malformation caused by partial chromosome 11q monosomy. Breakpoints typically arise in 11q23.3 with deletions extending to the telomere. More than 150 cases have been reported in the literature, with 110 of these being part of a single prospective study. The deletion of variable size gives rise to several phenotypes of varying severity, including multiple dysmorphic features, congenital heart defects and Paris-Trousseau thrombocytopenia (see this term). Mental retardation goes from normal to moderate. Patients with mild cognitive dysfunction have near-normal receptive language but moderately impaired expressive language function. Other common phenotypes include ophthalmologic, gastrointestinal symptoms, short stature, genitourinary problems, as well as fine and gross motor delays. Clinical management includes baseline cardiac evaluation and demonstration of the severe platelet dysfunction occurring in most cases. Although the decreased platelet count tends to resolve over time, platelet dysfunction is persistent, thus placing these patients at lifelong risk for bleeding. Studies of 11q deletion breakpoints reveal an interesting etiology; a folate-sensitive fragile site was shown to cause the deletions found in some patients, and breakpoints generally appear to cluster with CCG-trinucleotide repeats. *Authors: Drs P. Grossfeld and C. Jones (July 2003)*. Update : 23/09/2007

Orphanet database access

Orphanet database access

Jacobsen syndrome Direct access to data Summary The 11q terminal deletion disorder (also called "Jacobsen syndrome'') is a recognized pattern of malformation caused by partial chromosome 11q monosomy. Breakpoints typically arise in 11q23.3 with deletions extending to the telomere. More than 150 cases have been reported in the literature, with 110 of these being part of a single prospective study. The deletion of variable size gives rise to several phenotypes of varying severity, including multiple dysmorphic features, congenital heart defects and Paris-Trousseau thrombocytopenia (see this term). Mental retardation goes from normal to moderate. Patients with mild cognitive dysfunction have near-normal receptive language but moderately impaired expressive language function. Other common phenotypes include ophthalmologic, gastrointestinal symptoms, short stature, genitourinary problems, as well as fine and gross motor delays. Clinical management includes baseline cardiac evaluation and demonstration of the severe platelet dysfunction occurring in most cases. Although the decreased platelet count tends to resolve over time, platelet dysfunction is persistent, thus placing these patients at lifelong risk for bleeding. Studies of 11q deletion breakpoints reveal an interesting etiology; a folate-sensitive fragile site was shown to cause the deletions found in some patients, and breakpoints generally appear to cluster with CCG-trinucleotide repeats. *Authors: Drs P. Grossfeld and C. Jones (July 2003)*. Update : 30/09/2007

Orphanet database access

Orphanet database access

Jacobsen syndrome Direct access to data Summary The 11q terminal deletion disorder (also called "Jacobsen syndrome'') is a recognized pattern of malformation caused by partial chromosome 11q monosomy. Breakpoints typically arise in 11q23.3 with deletions extending to the telomere. More than 150 cases have been reported in the literature, with 110 of these being part of a single prospective study. The deletion of variable size gives rise to several phenotypes of varying severity, including multiple dysmorphic features, congenital heart defects and Paris-Trousseau thrombocytopenia (see this term). Mental retardation goes from normal to moderate. Patients with mild cognitive dysfunction have near-normal receptive language but moderately impaired expressive language function. Other common phenotypes include ophthalmologic, gastrointestinal symptoms, short stature, genitourinary problems, as well as fine and gross motor delays. Clinical management includes baseline cardiac evaluation and demonstration of the severe platelet dysfunction occurring in most cases. Although the decreased platelet count tends to resolve over time, platelet dysfunction is persistent, thus placing these patients at lifelong risk for bleeding. Studies of 11q deletion breakpoints reveal an interesting etiology; a folate-sensitive fragile site was shown to cause the deletions found in some patients, and breakpoints generally appear to cluster with CCG-trinucleotide repeats. *Authors: Drs P. Grossfeld and C. Jones (July 2003)*. Update : 07/10/2007

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Orphanet database access

Jacobsen syndrome Direct access to data Summary The 11q terminal deletion disorder (also called "Jacobsen syndrome'') is a recognized pattern of malformation caused by partial chromosome 11q monosomy. Breakpoints typically arise in 11q23.3 with deletions extending to the telomere. More than 150 cases have been reported in the literature, with 110 of these being part of a single prospective study. The deletion of variable size gives rise to several phenotypes of varying severity, including multiple dysmorphic features, congenital heart defects and Paris-Trousseau thrombocytopenia (see this term). Mental retardation goes from normal to moderate. Patients with mild cognitive dysfunction have near-normal receptive language but moderately impaired expressive language function. Other common phenotypes include ophthalmologic, gastrointestinal symptoms, short stature, genitourinary problems, as well as fine and gross motor delays. Clinical management includes baseline cardiac evaluation and demonstration of the severe platelet dysfunction occurring in most cases. Although the decreased platelet count tends to resolve over time, platelet dysfunction is persistent, thus placing these patients at lifelong risk for bleeding. Studies of 11q deletion breakpoints reveal an interesting etiology; a folate-sensitive fragile site was shown to cause the deletions found in some patients, and breakpoints generally appear to cluster with CCG-trinucleotide repeats. *Authors: Drs P. Grossfeld and C. Jones (July 2003)*. Update : 14/10/2007

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Orphanet database access

Jacobsen syndrome Direct access to data Summary The 11q terminal deletion disorder (also called "Jacobsen syndrome'') is a recognized pattern of malformation caused by partial chromosome 11q monosomy. Breakpoints typically arise in 11q23.3 with deletions extending to the telomere. More than 150 cases have been reported in the literature, with 110 of these being part of a single prospective study. The deletion of variable size gives rise to several phenotypes of varying severity, including multiple dysmorphic features, congenital heart defects and Paris-Trousseau thrombocytopenia (see this term). Mental retardation goes from normal to moderate. Patients with mild cognitive dysfunction have near-normal receptive language but moderately impaired expressive language function. Other common phenotypes include ophthalmologic, gastrointestinal symptoms, short stature, genitourinary problems, as well as fine and gross motor delays. Clinical management includes baseline cardiac evaluation and demonstration of the severe platelet dysfunction occurring in most cases. Although the decreased platelet count tends to resolve over time, platelet dysfunction is persistent, thus placing these patients at lifelong risk for bleeding. Studies of 11q deletion breakpoints reveal an interesting etiology; a folate-sensitive fragile site was shown to cause the deletions found in some patients, and breakpoints generally appear to cluster with CCG-trinucleotide repeats. *Authors: Drs P. Grossfeld and C. Jones (July 2003)*. Update : 21/10/2007

Orphanet database access

Orphanet database access

Jacobsen syndrome Direct access to data Summary The 11q terminal deletion disorder (also called "Jacobsen syndrome'') is a recognized pattern of malformation caused by partial chromosome 11q monosomy. Breakpoints typically arise in 11q23.3 with deletions extending to the telomere. More than 150 cases have been reported in the literature, with 110 of these being part of a single prospective study. The deletion of variable size gives rise to several phenotypes of varying severity, including multiple dysmorphic features, congenital heart defects and Paris-Trousseau thrombocytopenia (see this term). Mental retardation goes from normal to moderate. Patients with mild cognitive dysfunction have near-normal receptive language but moderately impaired expressive language function. Other common phenotypes include ophthalmologic, gastrointestinal symptoms, short stature, genitourinary problems, as well as fine and gross motor delays. Clinical management includes baseline cardiac evaluation and demonstration of the severe platelet dysfunction occurring in most cases. Although the decreased platelet count tends to resolve over time, platelet dysfunction is persistent, thus placing these patients at lifelong risk for bleeding. Studies of 11q deletion breakpoints reveal an interesting etiology; a folate-sensitive fragile site was shown to cause the deletions found in some patients, and breakpoints generally appear to cluster with CCG-trinucleotide repeats. *Authors: Drs P. Grossfeld and C. Jones (July 2003)*. Update : 28/10/2007

Orphanet database access

Orphanet database access

Jacobsen syndrome Direct access to data Summary The 11q terminal deletion disorder (also called "Jacobsen syndrome'') is a recognized pattern of malformation caused by partial chromosome 11q monosomy. Breakpoints typically arise in 11q23.3 with deletions extending to the telomere. More than 150 cases have been reported in the literature, with 110 of these being part of a single prospective study. The deletion of variable size gives rise to several phenotypes of varying severity, including multiple dysmorphic features, congenital heart defects and Paris-Trousseau thrombocytopenia (see this term). Mental retardation goes from normal to moderate. Patients with mild cognitive dysfunction have near-normal receptive language but moderately impaired expressive language function. Other common phenotypes include ophthalmologic, gastrointestinal symptoms, short stature, genitourinary problems, as well as fine and gross motor delays. Clinical management includes baseline cardiac evaluation and demonstration of the severe platelet dysfunction occurring in most cases. Although the decreased platelet count tends to resolve over time, platelet dysfunction is persistent, thus placing these patients at lifelong risk for bleeding. Studies of 11q deletion breakpoints reveal an interesting etiology; a folate-sensitive fragile site was shown to cause the deletions found in some patients, and breakpoints generally appear to cluster with CCG-trinucleotide repeats. *Authors: Drs P. Grossfeld and C. Jones (July 2003)*. Update : 04/11/2007

Orphanet database access

Orphanet database access

Jacobsen syndrome Direct access to data Summary The 11q terminal deletion disorder (also called "Jacobsen syndrome'') is a recognized pattern of malformation caused by partial chromosome 11q monosomy. Breakpoints typically arise in 11q23.3 with deletions extending to the telomere. More than 150 cases have been reported in the literature, with 110 of these being part of a single prospective study. The deletion of variable size gives rise to several phenotypes of varying severity, including multiple dysmorphic features, congenital heart defects and Paris-Trousseau thrombocytopenia (see this term). Mental retardation goes from normal to moderate. Patients with mild cognitive dysfunction have near-normal receptive language but moderately impaired expressive language function. Other common phenotypes include ophthalmologic, gastrointestinal symptoms, short stature, genitourinary problems, as well as fine and gross motor delays. Clinical management includes baseline cardiac evaluation and demonstration of the severe platelet dysfunction occurring in most cases. Although the decreased platelet count tends to resolve over time, platelet dysfunction is persistent, thus placing these patients at lifelong risk for bleeding. Studies of 11q deletion breakpoints reveal an interesting etiology; a folate-sensitive fragile site was shown to cause the deletions found in some patients, and breakpoints generally appear to cluster with CCG-trinucleotide repeats. *Authors: Drs P. Grossfeld and C. Jones (July 2003)*. Update : 18/11/2007

Orphanet database access

Orphanet database access

Jacobsen syndrome Direct access to data Summary The 11q terminal deletion disorder (also called "Jacobsen syndrome'') is a recognized pattern of malformation caused by partial chromosome 11q monosomy. Breakpoints typically arise in 11q23.3 with deletions extending to the telomere. More than 150 cases have been reported in the literature, with 110 of these being part of a single prospective study. The deletion of variable size gives rise to several phenotypes of varying severity, including multiple dysmorphic features, congenital heart defects and Paris-Trousseau thrombocytopenia (see this term). Mental retardation goes from normal to moderate. Patients with mild cognitive dysfunction have near-normal receptive language but moderately impaired expressive language function. Other common phenotypes include ophthalmologic, gastrointestinal symptoms, short stature, genitourinary problems, as well as fine and gross motor delays. Clinical management includes baseline cardiac evaluation and demonstration of the severe platelet dysfunction occurring in most cases. Although the decreased platelet count tends to resolve over time, platelet dysfunction is persistent, thus placing these patients at lifelong risk for bleeding. Studies of 11q deletion breakpoints reveal an interesting etiology; a folate-sensitive fragile site was shown to cause the deletions found in some patients, and breakpoints generally appear to cluster with CCG-trinucleotide repeats. *Authors: Drs P. Grossfeld and C. Jones (July 2003)*. Update : 25/11/2007

Orphanet database access

Orphanet database access

Jacobsen syndrome Direct access to data Summary The 11q terminal deletion disorder (also called "Jacobsen syndrome'') is a recognized pattern of malformation caused by partial chromosome 11q monosomy. Breakpoints typically arise in 11q23.3 with deletions extending to the telomere. More than 150 cases have been reported in the literature, with 110 of these being part of a single prospective study. The deletion of variable size gives rise to several phenotypes of varying severity, including multiple dysmorphic features, congenital heart defects and Paris-Trousseau thrombocytopenia (see this term). Mental retardation goes from normal to moderate. Patients with mild cognitive dysfunction have near-normal receptive language but moderately impaired expressive language function. Other common phenotypes include ophthalmologic, gastrointestinal symptoms, short stature, genitourinary problems, as well as fine and gross motor delays. Clinical management includes baseline cardiac evaluation and demonstration of the severe platelet dysfunction occurring in most cases. Although the decreased platelet count tends to resolve over time, platelet dysfunction is persistent, thus placing these patients at lifelong risk for bleeding. Studies of 11q deletion breakpoints reveal an interesting etiology; a folate-sensitive fragile site was shown to cause the deletions found in some patients, and breakpoints generally appear to cluster with CCG-trinucleotide repeats. *Authors: Drs P. Grossfeld and C. Jones (July 2003)*. Update : 02/12/2007

Orphanet database access

Orphanet database access

Jacobsen syndrome Direct access to data Summary The 11q terminal deletion disorder (also called "Jacobsen syndrome'') is a recognized pattern of malformation caused by partial chromosome 11q monosomy. Breakpoints typically arise in 11q23.3 with deletions extending to the telomere. More than 150 cases have been reported in the literature, with 110 of these being part of a single prospective study. The deletion of variable size gives rise to several phenotypes of varying severity, including multiple dysmorphic features, congenital heart defects and Paris-Trousseau thrombocytopenia (see this term). Mental retardation goes from normal to moderate. Patients with mild cognitive dysfunction have near-normal receptive language but moderately impaired expressive language function. Other common phenotypes include ophthalmologic, gastrointestinal symptoms, short stature, genitourinary problems, as well as fine and gross motor delays. Clinical management includes baseline cardiac evaluation and demonstration of the severe platelet dysfunction occurring in most cases. Although the decreased platelet count tends to resolve over time, platelet dysfunction is persistent, thus placing these patients at lifelong risk for bleeding. Studies of 11q deletion breakpoints reveal an interesting etiology; a folate-sensitive fragile site was shown to cause the deletions found in some patients, and breakpoints generally appear to cluster with CCG-trinucleotide repeats. *Authors: Drs P. Grossfeld and C. Jones (July 2003)*. Update : 09/12/2007

Orphanet database access

Orphanet database access

Jacobsen syndrome Direct access to data Summary The 11q terminal deletion disorder (also called "Jacobsen syndrome'') is a recognized pattern of malformation caused by partial chromosome 11q monosomy. Breakpoints typically arise in 11q23.3 with deletions extending to the telomere. More than 150 cases have been reported in the literature, with 110 of these being part of a single prospective study. The deletion of variable size gives rise to several phenotypes of varying severity, including multiple dysmorphic features, congenital heart defects and Paris-Trousseau thrombocytopenia (see this term). Mental retardation goes from normal to moderate. Patients with mild cognitive dysfunction have near-normal receptive language but moderately impaired expressive language function. Other common phenotypes include ophthalmologic, gastrointestinal symptoms, short stature, genitourinary problems, as well as fine and gross motor delays. Clinical management includes baseline cardiac evaluation and demonstration of the severe platelet dysfunction occurring in most cases. Although the decreased platelet count tends to resolve over time, platelet dysfunction is persistent, thus placing these patients at lifelong risk for bleeding. Studies of 11q deletion breakpoints reveal an interesting etiology; a folate-sensitive fragile site was shown to cause the deletions found in some patients, and breakpoints generally appear to cluster with CCG-trinucleotide repeats. *Authors: Drs P. Grossfeld and C. Jones (July 2003)*. Update : 16/12/2007

Orphanet database access

Orphanet database access

Jacobsen syndrome Direct access to data Summary The 11q terminal deletion disorder (also called "Jacobsen syndrome'') is a recognized pattern of malformation caused by partial chromosome 11q monosomy. Breakpoints typically arise in 11q23.3 with deletions extending to the telomere. More than 150 cases have been reported in the literature, with 110 of these being part of a single prospective study. The deletion of variable size gives rise to several phenotypes of varying severity, including multiple dysmorphic features, congenital heart defects and Paris-Trousseau thrombocytopenia (see this term). Mental retardation goes from normal to moderate. Patients with mild cognitive dysfunction have near-normal receptive language but moderately impaired expressive language function. Other common phenotypes include ophthalmologic, gastrointestinal symptoms, short stature, genitourinary problems, as well as fine and gross motor delays. Clinical management includes baseline cardiac evaluation and demonstration of the severe platelet dysfunction occurring in most cases. Although the decreased platelet count tends to resolve over time, platelet dysfunction is persistent, thus placing these patients at lifelong risk for bleeding. Studies of 11q deletion breakpoints reveal an interesting etiology; a folate-sensitive fragile site was shown to cause the deletions found in some patients, and breakpoints generally appear to cluster with CCG-trinucleotide repeats. *Authors: Drs P. Grossfeld and C. Jones (July 2003)*. Update : 23/12/2007

Orphanet database access

Orphanet database access

Jacobsen syndrome Direct access to data Summary The 11q terminal deletion disorder (also called "Jacobsen syndrome'') is a recognized pattern of malformation caused by partial chromosome 11q monosomy. Breakpoints typically arise in 11q23.3 with deletions extending to the telomere. More than 150 cases have been reported in the literature, with 110 of these being part of a single prospective study. The deletion of variable size gives rise to several phenotypes of varying severity, including multiple dysmorphic features, congenital heart defects and Paris-Trousseau thrombocytopenia (see this term). Mental retardation goes from normal to moderate. Patients with mild cognitive dysfunction have near-normal receptive language but moderately impaired expressive language function. Other common phenotypes include ophthalmologic, gastrointestinal symptoms, short stature, genitourinary problems, as well as fine and gross motor delays. Clinical management includes baseline cardiac evaluation and demonstration of the severe platelet dysfunction occurring in most cases. Although the decreased platelet count tends to resolve over time, platelet dysfunction is persistent, thus placing these patients at lifelong risk for bleeding. Studies of 11q deletion breakpoints reveal an interesting etiology; a folate-sensitive fragile site was shown to cause the deletions found in some patients, and breakpoints generally appear to cluster with CCG-trinucleotide repeats. *Authors: Drs P. Grossfeld and C. Jones (July 2003)*. Update : 30/12/2007

Orphanet database access

Orphanet database access

Jacobsen syndrome Direct access to data Summary The 11q terminal deletion disorder (also called "Jacobsen syndrome'') is a recognized pattern of malformation caused by partial chromosome 11q monosomy. Breakpoints typically arise in 11q23.3 with deletions extending to the telomere. More than 150 cases have been reported in the literature, with 110 of these being part of a single prospective study. The deletion of variable size gives rise to several phenotypes of varying severity, including multiple dysmorphic features, congenital heart defects and Paris-Trousseau thrombocytopenia (see this term). Mental retardation goes from normal to moderate. Patients with mild cognitive dysfunction have near-normal receptive language but moderately impaired expressive language function. Other common phenotypes include ophthalmologic, gastrointestinal symptoms, short stature, genitourinary problems, as well as fine and gross motor delays. Clinical management includes baseline cardiac evaluation and demonstration of the severe platelet dysfunction occurring in most cases. Although the decreased platelet count tends to resolve over time, platelet dysfunction is persistent, thus placing these patients at lifelong risk for bleeding. Studies of 11q deletion breakpoints reveal an interesting etiology; a folate-sensitive fragile site was shown to cause the deletions found in some patients, and breakpoints generally appear to cluster with CCG-trinucleotide repeats. *Authors: Drs P. Grossfeld and C. Jones (July 2003)*. Update : 06/01/2008

Orphanet database access

Orphanet database access

Jacobsen syndrome Direct access to data Summary The 11q terminal deletion disorder (also called "Jacobsen syndrome'') is a recognized pattern of malformation caused by partial chromosome 11q monosomy. Breakpoints typically arise in 11q23.3 with deletions extending to the telomere. More than 150 cases have been reported in the literature, with 110 of these being part of a single prospective study. The deletion of variable size gives rise to several phenotypes of varying severity, including multiple dysmorphic features, congenital heart defects and Paris-Trousseau thrombocytopenia (see this term). Mental retardation goes from normal to moderate. Patients with mild cognitive dysfunction have near-normal receptive language but moderately impaired expressive language function. Other common phenotypes include ophthalmologic, gastrointestinal symptoms, short stature, genitourinary problems, as well as fine and gross motor delays. Clinical management includes baseline cardiac evaluation and demonstration of the severe platelet dysfunction occurring in most cases. Although the decreased platelet count tends to resolve over time, platelet dysfunction is persistent, thus placing these patients at lifelong risk for bleeding. Studies of 11q deletion breakpoints reveal an interesting etiology; a folate-sensitive fragile site was shown to cause the deletions found in some patients, and breakpoints generally appear to cluster with CCG-trinucleotide repeats. *Authors: Drs P. Grossfeld and C. Jones (July 2003)*. Update : 13/01/2008

Orphanet database access

Orphanet database access

Jacobsen syndrome Direct access to data Summary The 11q terminal deletion disorder (also called "Jacobsen syndrome'') is a recognized pattern of malformation caused by partial chromosome 11q monosomy. Breakpoints typically arise in 11q23.3 with deletions extending to the telomere. More than 150 cases have been reported in the literature, with 110 of these being part of a single prospective study. The deletion of variable size gives rise to several phenotypes of varying severity, including multiple dysmorphic features, congenital heart defects and Paris-Trousseau thrombocytopenia (see this term). Mental retardation goes from normal to moderate. Patients with mild cognitive dysfunction have near-normal receptive language but moderately impaired expressive language function. Other common phenotypes include ophthalmologic, gastrointestinal symptoms, short stature, genitourinary problems, as well as fine and gross motor delays. Clinical management includes baseline cardiac evaluation and demonstration of the severe platelet dysfunction occurring in most cases. Although the decreased platelet count tends to resolve over time, platelet dysfunction is persistent, thus placing these patients at lifelong risk for bleeding. Studies of 11q deletion breakpoints reveal an interesting etiology; a folate-sensitive fragile site was shown to cause the deletions found in some patients, and breakpoints generally appear to cluster with CCG-trinucleotide repeats. *Authors: Drs P. Grossfeld and C. Jones (July 2003)*. Update : 20/01/2008

Orphanet database access

Orphanet database access

Jacobsen syndrome Direct access to data Summary The 11q terminal deletion disorder (also called "Jacobsen syndrome'') is a recognized pattern of malformation caused by partial chromosome 11q monosomy. Breakpoints typically arise in 11q23.3 with deletions extending to the telomere. More than 150 cases have been reported in the literature, with 110 of these being part of a single prospective study. The deletion of variable size gives rise to several phenotypes of varying severity, including multiple dysmorphic features, congenital heart defects and Paris-Trousseau thrombocytopenia (see this term). Mental retardation goes from normal to moderate. Patients with mild cognitive dysfunction have near-normal receptive language but moderately impaired expressive language function. Other common phenotypes include ophthalmologic, gastrointestinal symptoms, short stature, genitourinary problems, as well as fine and gross motor delays. Clinical management includes baseline cardiac evaluation and demonstration of the severe platelet dysfunction occurring in most cases. Although the decreased platelet count tends to resolve over time, platelet dysfunction is persistent, thus placing these patients at lifelong risk for bleeding. Studies of 11q deletion breakpoints reveal an interesting etiology; a folate-sensitive fragile site was shown to cause the deletions found in some patients, and breakpoints generally appear to cluster with CCG-trinucleotide repeats. *Authors: Drs P. Grossfeld and C. Jones (July 2003)*. Update : 27/01/2008

Orphanet database access

Orphanet database access

Jacobsen syndrome Direct access to data Summary The 11q terminal deletion disorder (also called "Jacobsen syndrome'') is a recognized pattern of malformation caused by partial chromosome 11q monosomy. Breakpoints typically arise in 11q23.3 with deletions extending to the telomere. More than 150 cases have been reported in the literature, with 110 of these being part of a single prospective study. The deletion of variable size gives rise to several phenotypes of varying severity, including multiple dysmorphic features, congenital heart defects and Paris-Trousseau thrombocytopenia (see this term). Mental retardation goes from normal to moderate. Patients with mild cognitive dysfunction have near-normal receptive language but moderately impaired expressive language function. Other common phenotypes include ophthalmologic, gastrointestinal symptoms, short stature, genitourinary problems, as well as fine and gross motor delays. Clinical management includes baseline cardiac evaluation and demonstration of the severe platelet dysfunction occurring in most cases. Although the decreased platelet count tends to resolve over time, platelet dysfunction is persistent, thus placing these patients at lifelong risk for bleeding. Studies of 11q deletion breakpoints reveal an interesting etiology; a folate-sensitive fragile site was shown to cause the deletions found in some patients, and breakpoints generally appear to cluster with CCG-trinucleotide repeats. *Authors: Drs P. Grossfeld and C. Jones (July 2003)*. Update : 03/02/2008

Orphanet database access

Orphanet database access

Jacobsen syndrome Direct access to data Summary The 11q terminal deletion disorder (also called "Jacobsen syndrome'') is a recognized pattern of malformation caused by partial chromosome 11q monosomy. Breakpoints typically arise in 11q23.3 with deletions extending to the telomere. More than 150 cases have been reported in the literature, with 110 of these being part of a single prospective study. The deletion of variable size gives rise to several phenotypes of varying severity, including multiple dysmorphic features, congenital heart defects and Paris-Trousseau thrombocytopenia (see this term). Mental retardation goes from normal to moderate. Patients with mild cognitive dysfunction have near-normal receptive language but moderately impaired expressive language function. Other common phenotypes include ophthalmologic, gastrointestinal symptoms, short stature, genitourinary problems, as well as fine and gross motor delays. Clinical management includes baseline cardiac evaluation and demonstration of the severe platelet dysfunction occurring in most cases. Although the decreased platelet count tends to resolve over time, platelet dysfunction is persistent, thus placing these patients at lifelong risk for bleeding. Studies of 11q deletion breakpoints reveal an interesting etiology; a folate-sensitive fragile site was shown to cause the deletions found in some patients, and breakpoints generally appear to cluster with CCG-trinucleotide repeats. *Authors: Drs P. Grossfeld and C. Jones (July 2003)*. Update : 10/02/2008

Orphanet database access

Orphanet database access

Jacobsen syndrome Direct access to data Summary The 11q terminal deletion disorder (also called "Jacobsen syndrome'') is a recognized pattern of malformation caused by partial chromosome 11q monosomy. Breakpoints typically arise in 11q23.3 with deletions extending to the telomere. More than 150 cases have been reported in the literature, with 110 of these being part of a single prospective study. The deletion of variable size gives rise to several phenotypes of varying severity, including multiple dysmorphic features, congenital heart defects and Paris-Trousseau thrombocytopenia (see this term). Mental retardation goes from normal to moderate. Patients with mild cognitive dysfunction have near-normal receptive language but moderately impaired expressive language function. Other common phenotypes include ophthalmologic, gastrointestinal symptoms, short stature, genitourinary problems, as well as fine and gross motor delays. Clinical management includes baseline cardiac evaluation and demonstration of the severe platelet dysfunction occurring in most cases. Although the decreased platelet count tends to resolve over time, platelet dysfunction is persistent, thus placing these patients at lifelong risk for bleeding. Studies of 11q deletion breakpoints reveal an interesting etiology; a folate-sensitive fragile site was shown to cause the deletions found in some patients, and breakpoints generally appear to cluster with CCG-trinucleotide repeats. *Authors: Drs P. Grossfeld and C. Jones (July 2003)*. Update : 17/02/2008

Orphanet database access

Orphanet database access

Jacobsen syndrome Direct access to data Summary The 11q terminal deletion disorder (also called "Jacobsen syndrome'') is a recognized pattern of malformation caused by partial chromosome 11q monosomy. Breakpoints typically arise in 11q23.3 with deletions extending to the telomere. More than 150 cases have been reported in the literature, with 110 of these being part of a single prospective study. The deletion of variable size gives rise to several phenotypes of varying severity, including multiple dysmorphic features, congenital heart defects and Paris-Trousseau thrombocytopenia (see this term). Mental retardation goes from normal to moderate. Patients with mild cognitive dysfunction have near-normal receptive language but moderately impaired expressive language function. Other common phenotypes include ophthalmologic, gastrointestinal symptoms, short stature, genitourinary problems, as well as fine and gross motor delays. Clinical management includes baseline cardiac evaluation and demonstration of the severe platelet dysfunction occurring in most cases. Although the decreased platelet count tends to resolve over time, platelet dysfunction is persistent, thus placing these patients at lifelong risk for bleeding. Studies of 11q deletion breakpoints reveal an interesting etiology; a folate-sensitive fragile site was shown to cause the deletions found in some patients, and br