SNAI2 and Waardenburg syndrome type 2: In the group of 57 individuals with WS type 2, mutations in 4 other causative subtype genes are 51.1% (24/47) in MITF, 19.1% (9/47) in SOX10, 6.4% (3/47) in EDN3, and 2.0% (1/47) in SNAI2. Compared to Pingault et al.' s review [18], in which the overall detection rate in WS type 2 is approximately 50%, our detection technology (73.7%, 42/57) has absolute advantages.