Waardenburg syndrome (WS) is a genetic disorder characterised by congenital hearing loss, dystopia canthorum (increased distance between the inner canthi), and abnormalities in pigmentation of the hair, skin, and eyes. There are four different types of Waardenburg Syndrome: types 1 and 2 are the most common types, whereas types 3 and 4 are relatively rare. Waardenburg syndrome type 2 (WS2) patients do not present with dystopia canthorum but have other typical WS features including pigmentation anomalies and varying degrees of sensorineural deafness.
WS2 is genetically heterogeneous and has several subtypes. Mutations in the MITF (microphthalmia-associated transcription factor) gene, located on chromosome 3p13, have been identified in some cases of WS2A. Other subtypes of WS2 are caused by mutations in the SNAI2 gene, SOX10 gene, or linked to loci on chromosomes 1p or 8p23.
Mullaney et al. (1998) reported a four month old Saudi girl with Waardenburg syndrome (WS2). She presented with nystagmus of two months' duration, and then she developed bilateral leucocoria. She had non-central, non-steady, and non-maintained fixation in her both eyes. Her right iris and lower half of the left iris were blue, while the upper half of her left iris was brown. She had bilateral central nuclear lens opacities. White hair in the anterior part of the scalp was present. She also had severe sensory neural hearing loss, fundus hypopigmentation, absent of dystopia canthroum, and congenital cataracts. Determining the inheritance pattern was not possible, because the parents did not provide any information about the family history and were unwilling to examine the other family members.