一个遗传性对称性色素异常症家系的ADAR基因变异分析CSCD

目的探讨1个遗传性对称性色素异常症(dyschromatosis symmetrica hereditaria, DSH)家系患者的临床特点及基因变异, 明确其致病原因。方法采集先证者及其母亲的外周血样, 应用PCR扩增结合Sanger测序的方法分别对先证者和母亲的ADAR基因进行变异分析, 确定疑似致病变异。同时以100例与本家系无关的正常人作为对照。结果该病例符合DSH的典型表现, 表现为发生在手背, 脚和面部色素沉着、色素减退斑、色素异常斑。Sanger测序显示家系先证者及其母亲均携带ADAR基因第9外显子c.2762+1G>T杂合变异, 100名健康对照均未发现上述变异。根据美国医学遗传学与基因组学学会指南, ADAR基因c.2762+1G>T剪接变异被判定为致病性(PVS1+PM2+PP4)。结论 ADAR基因c.2762+1G>T变异可能为该家系患者的致病原因, 上述结果丰富了ADAR基因的变异谱。

Analysis of ADAR gene variant in a Chinese pedigree affected with dyschromatosis symmetrica hereditariaCSCD

Objective To analyze the clinical features and genetic basis for a Chinese pedigree affected with hereditary dyschromatosis symmetrica hereditaria (DSH). Methods Peripheral blood samples of the proband and his mother were collected and subjected to PCR and Sanger sequencing. Results The patient has conformed to the typical pattern of DSH and manifested with hyperpigmentation, hypo- and hyperpigmentation spots on the back of hands, feet and face. Sanger sequencing confirmed that the proband and his mother have both harbored heterozygous splicing variant c. 2762+ 1G>T in exon 9 of the ADAR gene, which was unreported previously. The same variant was not detected among 100 healthy controls. According to the guidelines of the American College of Medical Genetics and Genomics, the variant was predicted to be pathogenic (PVS1+ PM2+ PP4). Conclusion The c. 2762+ 1G>T variant of the ADAR gene probably underlay the DSH in this pedigree. Above finding has enriched the spectrum of ADAR gene mutations. © 2022 West China University of Medical Sciences. All rights reserved.