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目的:对1个X连锁视网膜劈裂症（XLRS）家系进行基因分析，观察其n RS1基因的突变位点。n 方法:回顾性临床研究。一个4代26人的XLRS家系中3例患者及12名家系成员纳入研究。其中，男性8名，女性7名。所有受试者均行眼科常规检查；3例患者中，行光相干断层扫描（OCT）检查2例。抽取所有受试者的外周静脉血，提取全基因组DNA，Panel测序法筛选潜在致病基因。利用软件工具对突变进行保守性分析、致病性分析和蛋白结构预测。并根据美国医学遗传学与基因组学学会（ACMG）指南分析基因突变的致病性。结果:先证者，3岁。OCT检查，双眼黄斑区视网膜内核层隆起囊腔样改变，被垂直或斜形桥状组织分割。先证者舅舅，32岁。OCT检查，左眼黄斑区萎缩；右眼黄斑区囊样隆起，被垂直或斜形桥状组织分割。先证者父母及其他家系成员10名眼底检查均未见异常。Panel测序结果显示，先证者（Ⅳ3）及2例患者（Ⅱ1、Ⅲ8）n RS1基因第5外显子上存在c.361C>T/p.Q121X半合子突变；其母亲为该基因杂合突变携带者，父亲无变异。该突变基因导致RS1蛋白提前终止，由原来编码224个氨基酸突变为120个氨基酸的截短蛋白。眼底检查正常的10人中，正常者6人；该基因突变携带者4人，均为女性。蛋白序列同源性分析结果显示，该突变位点在12种哺乳动物中均高度保守。RS1蛋白三维结构分析结果显示，突变后的蛋白C端氨基酸序列缺失>50%。ACMG指南分析结果显示，该突变为致病性突变。n 结论:该XLRS家系n RS1基因突变位点c.361C>T/p.Q121X为XLRS新的突变位点。n “,”Objective:To study the characteristics of the genotype and phenotypic in a family with X-linked retinoschisis (XLRS) due to n RS1 mutation.n Methods:A retrospective clinical study. An XLRS family of 4 generations of 26 people were included in the study. Among them, 8 participants were males and 7 participants were females. Routine ophthalmologic examination was performed on 3 patients in the family including the proband and 12 patients with normal phenotype. Optical coherence tomography was performed in 2 of the 3 patients. Peripheral venous blood was extracted from all participants, whole-genome DNA was extracted, and potential pathogenic genes were screened by Panel sequencing. Conservative analysis, pathogenicity analysis and protein structure prediction were carried out by software tools. The pathogenicity of gene mutations was analyzed according to the American Society of Medical Genetics and Genomics (ACMG) guidelines.Results:The proband was 3 years old. Optical coherence tomography (OCT) examination showed that the retinal core layer in the macular area of both eyes had a cystic change, which was segmented by vertical or oblique bridging tissue. The proband\'s uncle was 32 years old. OCT examination showed atrophy in the macular area of the left eye. The macular area of the right eye was cystoid, segmented by vertical or oblique bridging tissue. No abnormality was found in the fundus examination of the proband\'s parents and 10 members of his family. Panel sequencing showed that c.361C>T/ p.Q121X hemizygous mutation was found in the fifth exon ofn RS1 gene in the proband (Ⅳ3) and 2 patients (Ⅱ1, Ⅲ8). The mother was a heterozygous mutation carrier of the gene, while the father had no mutation. The mutant gene causes premature termination of n RS1, a truncated protein encoding 224 amino acids to 120 amino acids. Of the 10 patients with normal fundus examination, 6 participants were normal. The mutation was carried by four people, which were women. Homology analysis of the protein sequence showed that the mutant site was highly conserved in 12 mammals. Three-dimensional structural analysis of RS1 protein showed that the c-terminal amino acid sequence of the mutant protein was more than 50% missing. Analysis of ACMG guidelines indicated that the mutation was pathogenic.n Conclusion:The RS1 mutation site c.361C>T/p.Q121X is a new mutation site of XLRS.