IRF6 and orofacial cleft: Different mutations in the IRF6 locus may increase the risk of syndromic and nonsyndromic forms of orofacial clefts; in humans, for example, mutations in the IRF6 gene are associated with Van der Wounde Syndrome (VWS) (OMIM # 119300) and Polipteal Pterygium syndrome (OMIM # 119500), rare orofacial cleft syndromes associated with lip pits, and cutaneous and limb defects [86,87].