长读取测序检测21羟化酶缺乏症患儿CYP21A1P/CYP21A2与TNXA/TNXB融合基因的类型及临床特点分析  

Detection and characterization of the types of CYP21A1P/CYP21A2 and TNXA/TNXB fused genes by long-read sequencing among children with Steroid 21-hydroxylase deficiency

作　　者：刘晖[1] 付青贤 李震 徐诗伊 杜玲玲 鄂慧姝 官丽梅 Liu Hui;Fu qingxian;Li Zhen;Xu Shiyi;Du Lingling;E Huishu;Guan Limei(Department of Endocrinology and Inborn Metabolic Diseases,Fujian Children′s Hospital(Fujian Branch of Shanghai Children′s Medical Center),College of Clinical Medicine for Obstetrics&Gynecology and Pediatrics,Fujian Medical University,Fuzhou,Fujian 350000,China)

机构地区：[1]福建省儿童医院(上海儿童医学中心福建医院)福建医科大学妇儿临床医学院内分泌遗传代谢科,福州350005

出　　处：《中华医学遗传学杂志》2024年第12期1416-1425,共10页Chinese Journal of Medical Genetics

基　　金：福建省自然科学基金(2023J011310)。

摘　　要：目的评估通过长读取测序(LRS)检测21-羟化酶缺陷症(21-OHD)患儿CYP21A1P/CYP21A2及TNXA/TNXB融合基因类型的效率并分析这类患儿的临床特征。方法应用LRS测序检测2022年11月至2023年9月就诊于福建省儿童医院内分泌科的30例通过临床诊断或传统的Sanger测序+多重连接探针扩增技术(MLPA)诊断的21-OHD患儿,比较2种方法的检测结果。收集并分析患儿的相关临床资料。本研究通过了福建省儿童医院医学伦理委员会的审查(批准号:2022ETKLR10024)。结果在30例21-OHD患儿中,LRS共检出11例(36.7%)携带CYP21A1P/CYP21A2和TNXA/TNXB融合基因,最常见的CYP21A1P/CYP21A2融合基因为CH-1(61.5%)。1例(3.3%)携带TNXA/TNXB CH-1。Sanger测序+MLPA共检出11人(36.7%)携带大片段缺失,其中最常见者为CYP21A2 exons 1-3 del(61.5%),其次为CYP21A2 exons 1-7 del(23.1%)。随访11例携带融合基因的患儿,6人表现为失盐型(SW),5人表现为单纯男性化型(SV),未发现非经典型(NC)型。4例女性患儿出现中枢性性早熟。1例携带TNXA/TNXB CH-1者具有CAH-X综合征的表现。结论与传统的Sanger测序和MLPA检测相比,LRS测序能够区分不同的CYP21A1P/CYP21A2和TNXA/TNXB融合基因类型,精确定位缺失的断裂点,直接确定其顺反式关系,而无需分析家系成员的基因型,为21-OHD分型提供可靠的基因诊断方法。部分融合基因保留了部分21-羟化酶的活性,携带者女性发生中枢性性早熟的风险更高。ObjectiveTo assess the diagnostic efficiency of long-read sequencing(LRS)for the determination of CYP21A1P/CYP21A2 and TNXA/TNXB fusion genotypes among children with 21-hydroxylase deficiency(21-OHD)and explore their clinical characteristics.MethodsLRS sequencing was carried out on 30 children diagnosed with 21-OHD at the Department of Endocrinology,Fujian Children′s Hospital between November 2022 and September 2023 by clinical symptoms or conventional Sanger sequencing combined with multiple ligation-dependent probe amplification(MLPA).The results of the two methods were compared.Clinical data of the children were collected and analyzed.This study has been approved by the Medical Ethic Committee of the Fujian Children Hospital(Ethic No.2022ETKLR10024).ResultsOf the 30 children with 21-OHD,11(36.7%)were found to carry CYP21A1P/CYP21A2 and TNXA/TNXB fusion genes by LRS.The most common type of fused CYP21A1P/CYP21A2 gene was CH-1(61.5%),and 1(3.3%)was found to harbor TNXA/TNXB CH-1.11 cases(36.7%)were found to carry large deletions by Sanger sequencing combined with MLPA,with the most common one being CYP21A2 exons 1-3 del(61.5%),which was followed by CYP21A2 exons 1-7 del(23.1%).Follow up of 11 patients carrying a fusion gene revealed that 6 were sale wasting(SW)types,5 were simple virilizing(SV)types,whilst no non-classical(NC)type was found.Four girls had presented with central precocious puberty(CPP).One child carrying TNXA/TNXB CH-1 had presented with CAH-X syndrome.ConclusionCompared with Sanger sequencing combined with MLPA detection method,LRS sequencing was able to differentiate the subtypes of CYP21A1P/CYP21A2 and TNXA/TNXB fusion genes,pinpoint the breakpoints of the deletions,and directly determine the cis-trans position without the need to analyze the genotype of the pedigree members,which has provided a reliable method for the typing of 21-OHD.As some fusion genes may retain 21-hydroxylase activity,female carriers may have a higher incidence of CPP.

关 键 词：21-羟化酶缺乏症 融合基因 长读取测序 

分 类 号：R725.8[医药卫生—儿科]