Lack of evidence for OSMR and RET gene mutations in a Chinese family with friction melanosis.

ABSTRACT

BACKGROUND: Friction melanosis (FM) is a common dermatological disorder. Although cases have been reported, familial FM is rare. FM and macular amyloidosis (MA) have been hypothesized to be identical clinical conditions, and cutaneous lichen amyloidosis (CLA) is linked to mutations in the OSMR (oncostatin M receptor) or RET (receptor tyrosine kinase) genes. AIM: To evaluate the OSMR and RET gene mutations in a Chinese family with FM. Methods. We investigated a family with FM with six affected members in four successive generations. All 17 exons of the OSMR and 19 exons of the RET genes were screened for mutation by PCR, and restriction enzyme digestion assays for RET codon 634 mutations were performed for selected members of the family. RESULTS: Based on the pedigree characteristics, we suggest an autosomal dominant mode of inheritance in this FM family. We did not detect any mutations in the OSMR or RET genes. CONCLUSIONS: We report a rare case of familial FM. Genes other than OSMR and RET may be involved in the pathogenesis of this family.