[Analysis of ADAR gene variants in a Chinese pedigree affected with Dyschromatosis symmetrica hereditaria in conjunct with developmental delay].

Abstract

To explore the clinical characteristics and genetic etiology for a Chinese pedigree affected with Dyschromatosis symmetrica hereditaria (DSH) in conjunct with developmental delay. A child who had presented at the First Affiliated Hospital of Zhengzhou University on May 28 2021 for abnormal skin pigmentation of the extremities and growth retardation for over 2 years was selected as the study subject. Clinical data of the child and his pedigree (11 individuals from three generations) was collected. The child was subjected to whole exome sequencing, and candidate variant was verified by Sanger sequencing. The child, a two-year-and-seven-month-old male, had hyper- and hypopigmentation on his hands, feet and face, in addition with delayed development. All members of his pedigree had typical presentation of DSH. A heterozygous c.2657G>A variant was found in exon 8 of the ADAR gene in the child, his mother, and elder sister. Based on the guidelines from the American College of Medical Genetics and Genomics (ACMG), the variant was predicted as likely pathogenic (PM1+PM2_Supporting+PP1+PP3). The c.2657G>A variant of the ADAR gene probably underlay the DSH in this pedigree.