[Identification of novel KIT gene mutations in two Chinese families with piebaldism]

To screen for potential mutations of KIT gene for two Chinese families affected with piebaldism in order to facilitate genetic counseling and assisted reproduction.

Peripheral blood samples were collected from 2 patients of family 1 and the proband and 3 unaffected members of family 2 for the extraction of DNA and RNA. PCR-sequencing and reverse transcription PCR-sequencing were used to screen KIT mutations.

All of the patients from family 1 were found to carry heterozygous IVS12+2-+7delinsACATCTTTA, a splicing mutation undocumented in the human gene mutation data base (HGMD) database. This mutation has resulted in c.1765-1779del in cDNA and p.Gly592Ala/del:E12, which has led to skipping of exon 12 and no expression of cDNA. The proband from family 2 has carried a heterozygous c.2401A>C mutation in KIT gene. The same mutation was not found in unaffected members.

We have attained definite diagnosis for both families, which has facilitated genetic counseling and assisted reproduction for our patients and their family members.