多发性骨骺发育不良一个家系的基因变异鉴定与致病机制分析  

Analysis of genetic variants and molecular pathogenesis in a Chinese pedigree affected with Multiple epiphyseal dysplasia

作　　者：李闪 绳月阳 王心雨 王莹 张砚卓 吴成爱 姜旭 Li Shan;Sheng Yueyang;Wang Xinyu;Wang Ying;Zhang Yanzhuo;Wu Cheng′ai;Jiang Xu(Beijing Institute of Trauma and Orthopedics,Beijing Jishuitan Hospital Affiliated to Capital Medical University,Beijing 100035,China;Department of Orthopedics,Beijing Jishuitan Hospital Affiliated to Capital Medical University,Beijing 100035,China)

机构地区：[1]首都医科大学附属北京积水潭医院北京市创伤骨科研究所分子骨科,北京100035 [2]首都医科大学附属北京积水潭医院矫形骨科,北京100035

出　　处：《中华医学遗传学杂志》2024年第7期807-811,共5页Chinese Journal of Medical Genetics

基　　金：国家自然科学基金(81472139);北京市卫生健康委员会基金(BJRITO-RDP-2023);北京积水潭医院自然基金培养计划(ZR202301)。

摘　　要：目的明确1个多发性骨骺发育不良(MED)家系的基因变异及遗传学病因。方法选取2020年9月13日于首都医科大学附属北京积水潭医院就诊的1个MED家系作为研究对象。收集该家系的临床资料,采集家系成员的外周血样,提取基因组DNA。对先证者进行全外显子组测序(WES)和生物信息学分析,确定变异位点,并通过Sanger测序法进行家系验证。分别构建SLC26A2基因野生型和变异型表达质粒,瞬时转染人原代软骨细胞,应用免疫荧光技术与CCK8试剂检测变异对于蛋白定位和细胞增殖的影响。结果WES与PCR-Sanger检测发现先证者携带SLC26A2基因复合杂合变异:c.484G>T(p.Val162Leu)和c.485_486delTG(p.Val162^(Glyfs*12)),分别遗传自其父亲与母亲。免疫荧光检测结果显示变异型SLC26A2^(Val162Leu)和SLC26A2^(Val162^(Glyfs*12)) 蛋白在人原代软骨细胞的细胞核和细胞质中均有分布,细胞增殖检测结果显示变异型SLC26A2^(Val162Leu)和SLC26A2^(Val162^(Glyfs*12)) 蛋白均能减少人原代软骨细胞的增殖。结论SLC26A2基因c.484G>T和c.485_486delTG变异均可影响人原代软骨细胞的增殖,可能是导致先证者患MED的遗传学病因。Objective To analyze the genetic variant and molecular pathogenesis in a Chinese pedigree affected with Multiple epiphyseal dysplasia(MED).Methods A MED pedigree which had presented at the Beijing Jishuitan Hospital Affiliated to Capital Medical University on September 13,2020 was selected as the study subject.Clinical data of the pedigree were collected.Peripheral blood samples were drawn from pedigree members for the extraction of genomic DNA.Whole exome sequencing(WES)was carried out for the pedigree.Candidate variant was verified by Sanger sequencing.Wild type and mutant SLC26A2 expression plasmids were constructed and transfected into human primary chondrocytes.The effect of the variants on the protein localization and cell proliferation was determined by immunofluorescence and CCK8 assays.Results WES and Sanger sequencing revealed that the proband has harbored compound heterozygous variants of the SLC26A2 gene,including a paternally derived c.484G>T(p.Val162Leu)missense variant and a maternally derived c.485_486delTG(p.Val162^(Glyfs*12))frameshifting variant.The SLC26A2WT and its mutant SLC26A2^(Val162Leu) and SLC26A2^(Val162^(Glyfs*12)) expression plasmids were distributed in the nuclei and cytoplasm of human primary chondrocytes.Compared with SLC26A2WT,the expressions of SLC26A2^(Val162Leu) and SLC26A2^(Val162^(Glyfs*12)) were decreased,along with reduced proliferation of human primary chondrocytes.Conclusion The c.484G>T and c.485_486delTG compound heterozygous variants of the SLC26A2 gene may affect the proliferation of human primary chondrocytes and underlay the pathogenesis of MED in this pedigree.

关 键 词：多发性骨骺发育不良 SLC26A2基因 基因变异 致病机制 

分 类 号：R681[医药卫生—骨科学]