Abstract: Objective To identify the gene locus and the mutation of DSRAD (double-stranded RNA adenosine deaminase) in a Chinese dyschromatosis symmetrica hereditaria(DSH) family. Methods After confirming the diagnosis of the DSH proband, the genomic DNA was extracted from the whole blood samples of every members of the pedigree. The DSRAD gene intervals were localized by linkage analysis and haplotype reconstruction. The mutation of DSRAD was detected by direct sequencing. Results The candidate gene was localized at the 1q region, consistent with the reported region. The direct sequencing results showed that there was a CAA→TAA transition at exon 2 of DSRAD in all affected family members, which consequently led to a nonsense mutation of Gln517Ter. Conclusion A nonsense mutation is found in the Chinese DSH family.

Key words: Dyschromatosis symmetrica hereditaria, Linkage(Genetics), Mutation