Orphanet: 1q21.1 microduplication syndrome

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1q21.1 microduplication syndrome

Disease definition

1q21.1 microduplication syndrome is a rare partial autosomal trisomy/tetrasomy with incomplete penetrance and variable expression characterized by macrocephaly, developmental delay, intellectual disability, psychiatric disturbances (autism spectrum disorder, attention deficit hyperactivity disorder, schizophrenia, mood disorders) and mild facial dysmorphism (high forehead, hypertelorism). Other associated features include congenital heart defects, hypotonia, short stature, scoliosis.


Classification level: Disorder
  • Synonym(s):
    • Dup(1)(q21.1)
    • Trisomy 1q21.1
  • Prevalence: <1 / 1 000 000
  • Inheritance: Autosomal dominant or Not applicable 
  • Age of onset: Infancy, Neonatal
  • ICD-10: Q92.3
  • OMIM: 612475
  • UMLS: C2675891
  • MeSH: -
  • GARD: 10591
  • MedDRA: -
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