Waardenburg Syndrome

Abstract

The syndrome described by Waardenburg in 1951 showed an association of craniofacial abnormalities, pigmentation disorders and congenital sensorineural hearing loss. The syndrome has subsequently been classified into four types. Types 1 and 2 are the most common and are dominantly inherited. Type 1 and Type 3 exhibit dystopia canthorum and mutations have been found in Pax3. Type 2 is distinguished by the absence of dystopia canthorum and in some families mutations have been found in MITF. Type 4 has features of Type 2 and is associated with Hirschsprung's disease; it is autosomal recessively inherited and has been shown to be caused by three genes. The clinical features of the syndrome show intraindividual and interfamilial variability. No clear relationship has been found between genotype and phenotype.