To detect mutations of ADAR gene in two pedigrees affected with dyschromatosis symmetrica hereditaria (DSH). Potential mutations of the ADAR gene were analyzed by Sanger sequencing of the probands from both pedigrees. Suspected mutations were validated by Sanger sequencing of other patients from both pedigrees as well as unrelated healthy individuals. A heterozygous nonsense mutation c.1325C>G (p.Ser442Ter) and a novel nonsense mutation c.1498C>T (p.Gln500Ter) were respectively identified in the ADAR gene among all patients from the two pedigrees but not among 200 healthy individuals. Mutations of the ADAR gene probably underlie the DSH in the two pedigrees. Above findings have enriched the spectrum of ADAR gene mutation.