单分子实时测序技术在1例21-羟化酶缺陷症患儿基因检测中的临床应用  

Clinical application of single molecule real-time sequencing technology in gene detection for a child with 21-hydroxylase deficiency

作　　者：赵炜[1] 王芳[1] 李加山 梁思颖 苗艳 姜楠[1] 李朔[1] ZHAO Wei;WANG Fang;LI Jiashan;LIANG Siying;MIAO Yan;JIANG Nan;LI Shuo(Genetic Testing Center,Qingdao Women and Children's Hospital Affiliated to Qingdao University,Qingdao 266034,Shandong,China)

机构地区：[1]青岛大学附属青岛妇女儿童医院基因检测中心,山东青岛266034

出　　处：《山东大学学报（医学版）》2024年第3期70-76,86,共8页Journal of Shandong University:Health Sciences

基　　金：青岛市医疗卫生重点学科建设项目。

摘　　要：目的应用单分子实时测序(single molecular real-time sequencing,SMRT)技术明确1例21-羟化酶缺陷症患儿的分子病因,并探讨SMRT用于临床基因检测的可行性。方法应用SMRT技术对先证者先天性肾上腺皮质增生症候选基因进行长读长测序,检测结果与多重连接探针扩增技术(multiplex ligation-dependent probe amplification,MLPA)和Sanger测序检测的家系结果进行比较。结果SMRT结果提示,先证者CYP21A2基因存在3个致病变异,先证者的一条染色体上串联排列两个重复的基因拷贝,分别为包含c.955C>T变异的CYP21A2基因和包含c.1069C>T变异的CYP21A2/CYP21A1P嵌合基因;另一染色体上的CYP21A2基因缺失。检测结果与家系MLPA+Sanger测序的结果相同,并明确了CYP21A2/CYP21A1P嵌合基因的排列方式。结论SMRT技术能够明确基因拷贝数变异、结构变异及嵌合基因的排列方式,可为21-羟化酶缺陷症遗传学诊断和携带者筛查提供更有价值的信息,具有较大的临床应用前景。Objective To determine the molecular etiology in a child with 21-hydroxylase deficiency using single molecular real-time sequencing(SMRT),and explore its clinical application for gene detection.Methods SMRT technology was applied to perform long-read sequencing on the candidate gene for congenital adrenal hyperplasia in the proband,and the results were compared to those obtained from multiplex ligation-dependent probe amplification(MLPA)and Sanger sequencing in the family.Results The SMRT results revealed three pathogenic variants in the proband's CYP21A2 gene,including two tandemly arranged gene copies on one chromosome(one CYP21A2 copy with c.955C>T mutation and the other CYP21A2/CYP21A1P chimeric copy with a c.1069C>T mutation),and a deletion of the CYP21A2 gene on the other chromosome.These variants were consistent with the results obtained by MLPA+Sanger sequencing in the family,and the arrangement of the CYP21A2/CYP21A1P chimeric gene was clarified.Conclusion SMRT technology can identify gene copy number variations,structure variations,and chimeric genes,providing more valuable information for genetic diagnosis and carrier screening of 21-hydroxylase deficiency.

关 键 词：单分子实时测序 长读长测序 CYP21A2基因 嵌合基因 基因重复 

分 类 号：R586.2[医药卫生—内分泌] R440[医药卫生—内科学]