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1p31p32 microdeletion syndrome

Disease definition

1p31p32 microdeletion syndrome is a rare chromosomal anomaly syndrome, resulting from the partial deletion of the short arm of chromosome 1, characterized by developmental delay, corpus callosum agenesis/hypoplasia and craniofacial dysmorphism, such as macrocephaly (caused by hydrocephalus or ventriculomegaly), low-set ears, anteverted nostrils and micrognathia. Urinary tract defects (e.g. vesicoureteral reflux, urinary incontinence) are also frequently associated. Other reported variable manifestations include hypotonia, tethered spinal cord, Chiari type I malformation and seizures.


Classification level: Disorder
  • Synonym(s):
    • Del(1)(p31p32)
    • Monosomy 1p31p32
  • Prevalence: <1 / 1 000 000
  • Inheritance: Unknown 
  • Age of onset: Neonatal
  • ICD-10: Q93.5
  • OMIM: 613735
  • UMLS: -
  • MeSH: -
  • GARD: -
  • MedDRA: -

Detailed information


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