Chotzen’s syndrome
a genetic condition characterized by an abnormally shaped head due to premature closing of one or more of the cranial sutures, usually involving the coronal suture (see craniosynostosis syndrome), and by webbing of the fingers and toes. Delayed development and learning difficulties can be associated with the disorder, but affected children often have average intelligence. Most cases are caused by mutations in the TWIST1 gene. In a small number of cases, when the cause is a chromosomal deletion instead of a mutation within the TWIST1 gene, affected children are much more likely to have intellectual disability, developmental delay, and learning difficulties. It is thought that a loss of other genes on chromosome 7 may be responsible for these additional features. Also called acrocephalosyndactyly Type III; Saethre–Chotzen syndrome. [F. Chotzen, German physician]