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X-linked mandibulofacial dysostosis

Disease definition

X-linked mandibulofacial dysostosis is an extremely rare multiple congenital abnormality syndrome that is characterized by microcephaly, malar hypoplasia with downslanting palpebral fissures, highly arched palate, apparently low-set and protruding ears, micrognathia, short stature, bilateral hearing loss, and learning disability. Occasionally, additional features have been observed such as bilateral cryptorchidism, cardiac valvular lesions, body asymmetry, and pectus excavatum.


Classification level: Disorder
  • Synonym(s):
    • Mandibulofacial dysostosis, Toriello type
    • X-linked branchial arch syndrome
    • X-linked mandibulofacial dysostosis with limb anomalies
  • Prevalence: <1 / 1 000 000
  • Inheritance: X-linked recessive 
  • Age of onset: Neonatal
  • ICD-10: Q75.4
  • OMIM: 301950
  • UMLS: C1844918
  • MeSH: -
  • GARD: 1002
  • MedDRA: -

Detailed information


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