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C syndrome

Disease definition

C syndrome is a rare multiple congenital anomaly/intellectual disability syndrome characterized by trigonocephaly and metopic suture synostosis, dysmorphic facial features, short neck, skeletal anomalies, and variable intellectual disability.


Classification level: Disorder
  • Synonym(s):
    • OTCS
    • Opitz C trigonocephaly
    • Opitz trigonocephaly C syndrome
    • Opitz trigonocephaly syndrome
    • Trigonocephaly C syndrome
  • Prevalence: 1-9 / 1 000 000
  • Inheritance: Not applicable or Unknown 
  • Age of onset: Neonatal, Antenatal
  • ICD-10: Q87.8
  • OMIM: 211750
  • UMLS: C0796095
  • MeSH: -
  • GARD: 5978
  • MedDRA: -

Detailed information


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