Objective: To identify the pathogenic mutation underlying piebaldism in a Chinese family.
Methods: A three-generation family showing an autosomal dominant transmission of piebaldism was recruited. Potential mutations of the KIT and SNAI2 genes were detected by PCR-amplification of the exons and exon-intron boundaries and direct sequencing.
Results: A heterozygous missense mutation, c.2585T>C, was identified in exon 18 of the KIT gene. The mutation, together with a c.2586G>C polymorphism, has led to substitution of Leucine by Proline at amino acid residue 862 (p.Leu862Pro) of the mast/stem cell growth factor receptor KIT. The same mutation was detected in all affected family members but not in dbSNP142, the 1000 Genomes draft database, or the Human Gene Mutation Database. No mutation of the SNAI2 gene was found.
Conclusion: The c.2585T>C (p.Leu862Pro) mutation in the KIT gene probably underlies the piebaldism phenotype in this family.