A rare neurodevelopmental disorder that is lethal in males and with characteristics of variable anomalies including external malformations (craniofacial and digital), and possible involvement of the central nervous system and of viscera (kidneys, pancreas and ovaries) in females. The disease is caused by mutations in the OFD1 gene (Xp22). A fraction of cases display genomic deletions. High penetrance has been reported but expression is highly variable. Follows an X-linked dominant pattern of inheritance. The gene mutations commonly occur de novo.