[Unilateral sensineural deafness associated with mutations in the PAX3-gene in Waardenburg syndrome type I].

Waardenburg syndrome (WS) type 1 occurs due to a mutation in the PAX3-gene on the long arm of chromosome 2. It is an autosomal dominant mutation with highly variable expression and high penetrance. Symptoms include the absence of melanocytes in the skin, hair, eyes and cochlea due to an early developmental disturbance in melancoytes from the neural crest. An inner ear disturbance is characteristic. Here we present a 4 year old girl with unilateral hearing loss, dystopia canthorum and partial albinism. Screening the entire PAX 3 gene revealed C64A und T164A mutations in exon I und II, both being missense mutations. Neither mutation has not been reported previously.