Identification of a novel c.2633_2634del CT variant of the ADAR gene in a patient with dyschromatosis symmetrica hereditaria

Objective To explore the genetic etiology of two unrelated patients with dyschromatosis symmetrica hereditaria. Methods Variant analysis of the ADAR gene was carried out by Sanger sequencing. Results Patient 1 was found to harbor a c. 2633_2634delCT (p.Ser878fs) in exon 8 of the ADAR gene. The same variant was not found among 100 unrelated individuals. No pathogenic variant of the ADAR gene was found in patient 2. Functional prediction of the ADAR c. 2633_2634delCT (p.Ser878fs) variant indicated it to be pathogenic by losing a catalytic structural domain. Conclusion The c. 2633_2634delCT (p.Ser878fs) variant of the ADAR gene probably underlies the pathogenesis of DSH in one of the patients. Key words: Dyschromatosis symmetrica hereditaria; ADAR gene; Variant