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Tetrasomy 9p

Disease definition

Tetrasomy 9p is a rare autosomal anomaly characterized by pre- and postnatal growth retardation, psychomotor delay, mild to moderate intellectual disability, hypotonia, microcephaly, dysmorphic features (ocular hypertelorism, low-set, malformed ears, bulbous/beaked nose, microretrognathia, enophthalmos/micropthalmia, epicanthus, strabismus), cleft lip/palate, skeletal abnormalities (hypoplastic nails/distal phalanges, short stature, short neck, contractures), congenital heart defects, renal and urogenital malformations (renal hypoplasia, genital hypoplasia, cryptorchidism).


Classification level: Disorder
  • Synonym(s):
    • Isochromosome 9p
  • Prevalence: <1 / 1 000 000
  • Inheritance: -
  • Age of onset: Antenatal, Neonatal
  • ICD-10: Q99.8
  • ICD-11: LD7Y
  • OMIM: -
  • UMLS: C0795832
  • MeSH: C538027
  • GARD: 42
  • MedDRA: -

Detailed information

General public

ERN produced/endorsed by ERN(s)   FSMR produced/endorsed by FSMR(s)
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