Van der Woude syndrome

Van Der Woude syndrome (VDWS) is a genetic disorder and congenital malformation. People with VDWS have cleft lip with or without cleft palate, pits or mucous cysts on the lower lip, hypodontia, a hypernasal voice, cleft or bifid uvula, syngnathia, narrow high arched palate, and ankyloglossia. Extraoral manifestations include limb anomalies, popliteal webs, accessory nipples, congenital heart defects, and Hirschsprung disease. However, Van der Woude syndrome has variable phenotypic expression. For example, some individuals affected by Van der Woude syndrome have isolated lip pits without any cleft syndrome. Affected individuals have normal intelligence. Ongoing research is being conducted to discover the genes involved in causing Van der Woude syndrome. A mutation in the gene IRF6 (interferon regulatory factor 6) has recently been discovered to be strongly associated with the disorder.

VDWS is the most common syndromic form of cleft lip and palate (CLP), accounting for 2% of all cleft lip and palate cases. Approximately 70% of cases of CLP are isolated, meaning that there are no other health issues present. However, cases of CLP with Van der Woude syndrome are considered syndromic because the individuals exhibit other abnormalities in addition to the cleft lip/palate. Van der Woude syndrome was first characterized in 1954.

Genetics
VDWS is an autosomal dominant or sporadic inheritance caused by mutations of the IRF6 gene, located on chromosome 1 at 1q32-q41. (Popliteal pterygium syndrome can also be caused by mutations of this gene.)