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Tetrasomy 18p

Disease definition

Tetrasomy 18p is a very rare structural chromosomal anomaly affecting multiple body systems and characterized clinically by craniofacial abnormalities, delayed development, cognitive impairment, changes in muscle tone, distinctive facial features, and rarely renal malformations.


Classification level: Disorder
  • Synonym(s):
    • Isochromosome 18p
  • Prevalence: 1-9 / 1 000 000
  • Inheritance: -
  • Age of onset: Neonatal, Antenatal
  • ICD-10: Q99.8
  • OMIM: 614290
  • UMLS: C0795868
  • MeSH: -
  • GARD: 35
  • MedDRA: -

Detailed information

Article for general public

The documents contained in this web site are presented for information purposes only. The material is in no way intended to replace professional medical care by a qualified specialist and should not be used as a basis for diagnosis or treatment.