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目的:分析中国汉族常染色体显性遗传视网膜色素变性(ADRP)一家系的致病基因及临床表型。方法:采用家系调查研究，收集2019年11月于河南省人民医院进行遗传咨询的中国汉族RP一家系，纳入该家系4代20名成员，包括9例患者和11名表型正常者，对部分家系成员进行视力、视野和眼底检查。收集该家系成员外周血样本，提取DNA，采用Ion Torrent PGM测序平台，对先证者进行包含43个与RP相关基因的外显子靶向测序，采用PCR和Sanger测序对变异位点进行验证。采用在线软件对变异位点进行蛋白功能预测。采用ClustalW2多重比对程序对变异位点的氨基酸序列进行比较。根据美国医学遗传学与基因组学学会(ACMG)遗传变异分类标准与指南分析变异的致病性。结果:该家系符合常染色体显性遗传。先证者，男，26岁，自幼双眼夜盲，视力右眼0.25，左眼0.5。双眼视网膜有骨细胞样色素沉着，视网膜血管变细，视盘颜色变淡。全视野视网膜电图检查显示，暗适应a波和b波峰值降低，明适应a波和b波峰值重度降低。其余家系成员患者均于7～10岁开始出现夜盲，约50岁时周边视力完全丧失，眼科检查均呈典型RP改变。基因检测结果显示，该家系视紫红质(n RHO)基因(NM_000539.3)5号外显子中存在1个杂合错义变异c.982delC(p.L328fs)。该变异可导致编码的RHO蛋白第328位氨基酸以后的21个氨基酸改变，使编码区由348个氨基酸增加到358个氨基酸，RHO蛋白结构发生改变；多个不同物种之间蛋白同源序列比对分析结果显示该位点高度保守。根据ACMG遗传变异分类标准与指南，该变异具有1个非常强的致病性证据PVS1，2个中等致病证据PM2，3个支持致病证据PP1、PP3、PP4，属于致病性变异。n 结论:RHO基因c.982delC变异为该家系的致病基因变异位点，该变异位点在中国汉族家系中首次报道。n “,”Objective:To analyze the pathogenic genes and clinical phenotypes of a Chinese Han family with autosomal dominant retinitis pigmentosa (ADRP).Methods:A pedigree investigation study was conducted, and a Chinese Han RP family that underwent genetic counseling in the Henan Provincial People's Hospital in November 2019 was collected.Twenty members of this family from 4 generations, including 9 patients and 11 phenotypically normal individuals, were enrolled.Visual acuity, peripheral visual field test and fundus examination were performed on some family members.Peripheral blood samples were collected from the family members, and DNA was extracted.Exon-targeted sequencing containing 43 genes associated with RP was performed on the proband using the Ion Torrent PGM sequencing platform.The mutations were verified by polymerase chain reaction and Sanger sequencing.Online software was applied to predict the protein function of the variant.The amino acid sequences of the variant loci were compared using the ClustalW2 multiplex alignment program.The pathogenicity of the variant was analyzed according to American College of Medical Genetics and Genomics (ACMG) criteria and guidelines for classification of genetic variant.This study adhered to the Declaration of Helsinki.The study protocol was approved by an Ethics Committee of Henan Provincial People's Hospital (No.HNEECKY-2019[15]).Results:The family was consistent with autosomal dominant inheritance.The proband, a 26-year-old male, had bilateral night blindness since childhood, with visual acuity of 0.25 in the right eye and 0.5 in the left eye.There was osteoblast-like pigmentation in his both retinas, thinned retinal vessels and pale optic disc.Full-field electroretinogram examination showed reduced scotopic a- and b-wave peaks and severely reduced photopic a- and b-wave peaks.The rest of the family began to develop night blindness when 7 to 10 years old, having complete loss of peripheral vision around 50 years of age, and typical RP changes were found in ophthalmic examination.Genetic testing revealed a heterozygous missense variant c. 982delC (p.L328fs) in exon 5 of the family's rhodopsin (n RHO) gene (NM_000539.3). This variant resulted in the change of 21 amino acids after amino acid 328 in the encoded RHO protein, increasing amino acids in the coding region from 348 to 358 and altering the structure of the RHO protein.The analysis of protein homology sequence alignment between several different species showed that the locus was highly conserved.According to the guidelines of the ACMG criteria and guidelines for classification of genetic variants, the variant was a pathogenic mutation because there were six evidences including one very strong evidence of pathogenicity PVS1, two moderate evidences of pathogenicity PM2 and three supporting evidences of pathogenicity, PP1, PP3 and PP4.n Conclusions:The c. 982delC variant in the n RHO gene is a pathogenic mutation in this pedigree, and this variant is reported for the first time in a Chinese Han family.n