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Xq21 microdeletion syndrome

Disease definition

An X-linked retinal dystrophy characterized by choroideremia, causing in affected males progressive nyctalopia and eventual central blindness. Obesity, moderate intellectual disability and congenital mixed (sensorineural and conductive) deafness are also observed. Female carriers show typical retinal changes indicative of the choroideremia carrier state.


Classification level: Disorder
  • Synonym(s):
    • Ayazi syndrome
    • Del(X)(q21)
    • Monosomy Xq21
  • Prevalence: <1 / 1 000 000
  • Inheritance: X-linked recessive 
  • Age of onset: Neonatal, Infancy
  • ICD-10: Q93.5
  • OMIM: 303110
  • UMLS: C1844836
  • MeSH: C537793
  • GARD: 369
  • MedDRA: -
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