Mutation analysis of DSRAD gene in a Chinese family with dyschromatosis symmetrica hereditaria.

Objective To detect the mutation of DSRAD gene in a Chinese family with dyschromatosis symmetrica hereditaria (DSH), and to explore new pathogenic mutation. Methods Members of a Chinese family with DSH, who had typical rash, were enrolled in this study, with normal physical development and intelligence, no obvious systematic symptoms. RT-PCR was applied to obtain DSRAD gene cDNA from human peripheral blood. Proper gene sequences were selected and compared with corresponding gene of human gene pool to identify suspicious sites, and new mutations were validated by single strand conformation. Results DSRAD gene sequence analysis confirmed the presence of nucleotide substitutions in the patient's chromosomes, with Q389Q replaced by A1167G. The encoding amino acid was still glutamic acid, which indicated a synonymous mutation. Single strand conformation confirmed that the DNA of the patients was of the same family, and that the healthy members and non-kinship members were not detected with the coding gene. Conclusion The abnormal changes of skin pigment may be due to synonymous mutations in gene. The mutation mechanism still needs further study.