Molecular Study of Three Lebanese and Syrian Patients with Waardenburg Syndrome and Report of Novel Mutations in the EDNRB and MITF Genes

Waardenburg syndrome (WS) is a genetic disorder charac- terized primarily by depigmentation of the skin and hair, het- erochromia of the irides, sensorineural deafness, and some- times by dystopia canthorum, and Hirschsprung disease. WS presents a large clinical and genetic heterogeneity. Four dif- ferent types have been individualized and linked to 5 differ- ent genes. We report 2 cases of WS type II and 1 case of WS type IV from Lebanon and Syria. The genetic studies revealed 2 novel mutations in the MITF gene of the WS type II cases and 1 novel homozygous mutation in the EDNRB gene of the WS type IV case. This is the first molecular study of patients from the Arab world. Additional cases will enable a more de- tailed description of the clinical spectrum of Waardenburg