850例耳聋基因筛查SLC26A4单杂合突变新生儿的基因型及合并第二突变位点者表型分析  

Analysis of genotypes on 850 newborns with SLC26A4 single-allele mutation and the phenotypes of those with second variant

作　　者：黄丽辉 赵雪雷 程晓华 于一丁 文铖 李悦 王现蕾 王雪瑶 阮宇 恩晖 Huang Lihui;Zhao Xuelei;Cheng Xiaohua;Yu Yiding;Wen Cheng;Li Yue;Wang Xianlei;Wang Xueyao;Ruan Yu;En Hui(Beijing Tongren Hospital,Capital Medical University,Beijing Institute of Otolaryngology,Key Laboratory of Otolaryngology Head and Neck Surgery,Ministry of Education(Capital Medical University),Beijing 100730,China;Department of Otolaryngology Head and Neck Surgery,Beijing Chaoyang Hospital,Capital Medical University,Beijing 100020,China)

机构地区：[1]首都医科大学附属北京同仁医院,北京市耳鼻咽喉科研究所,耳鼻咽喉头颈科学教育部重点实验室(首都医科大学),北京100730 [2]首都医科大学附属北京朝阳医院耳鼻咽喉头颈外科,北京100020

出　　处：《中华耳鼻咽喉头颈外科杂志》2023年第2期117-125,共9页Chinese Journal of Otorhinolaryngology Head and Neck Surgery

基　　金：国家自然科学基金面上项目(81870730,82071064);首都卫生发展科研专项(首发2022-2-1092);国家重点研发计划项目(2018YFC1002200)。

摘　　要：目的明确耳聋基因筛查SLC26A4单杂合突变新生儿合并第二突变位点的情况,分析SLC26A4突变基因型与听力表型的对应关系。方法研究对象为2015年4月至2019年12月在北京市出生、晶芯九项或十五项遗传性耳聋基因芯片筛查结果为SLC26A4单杂合突变的新生儿个体,共850例,其中男468例、女382例。采用三步耳聋基因测序:第一步,SLC26A4基因全外显子及剪接位点测序;第二步,SLC26A4基因启动子、FOXI1基因和KCNJ10基因全外显子测序;第三步,SLC26A4基因拷贝数变异检测。对三步检测发现的所有合并第二突变位点者,采集新生儿听力筛查结果,并进行声导抗、听性脑干反应和听性稳态反应等听力学检查。对新发现或争议(意义不明)突变位点,检索DVD、ClinVar和Mutation Taster等国际耳聋基因数据库或软件,依据美国医学遗传学与基因组学学会(American College of Medical Genetics and Genomics,ACMG)指南,对突变位点的致病性进行预测。整理SLC26A4单杂合突变新生儿合并第二突变位点数据,分析SLC26A4基因型及听力表型的对应关系。结果850例患儿确诊年龄中位数为4个月。第一步850例患儿测序,共检出第二突变位点32例(3.76%,32/850),包括明确致病突变位点18例(2.12%,8/850);第二步832例患儿测序,检出KCNJ10基因错义突变8例,未检出FOXI1基因错义突变及SLC26A4基因启动子异常;第三步824例测序结果均为阴性。合并明确第二致病突变位点者18例,其中新生儿听力筛查未通过16例(16/18),双耳均通过筛查2例(2/18);听力损失程度:极重度听力损失18耳(18/36),重度听力损失13耳(13/36),中度听力损失5耳(5/36);听力曲线类型:高频下降型17耳(17/36),平坦型14耳(14/36),无法判别3耳(3/36),U型2耳(2/36)。其他基因型22例,包括合并争议(意义不明)或新发现可能良性突变位点者9例、合并KCNJ10双基因杂合突变8例和同链双杂合突变5例,这22例患儿新生儿听力�Objective To clarify the phenotypes of the newborns with SLC26A4 single-allele mutation in deafness genetic screening and second variant;to analyze the SLC26A4 genotype and hearing phenotype.Methods 850 newborns born in Beijing from April 2015 to December 2019 were included and there were 468 males and 382 females.They received genetic deafness screening for 9 or 15 variants,with the result of SLC26A4 single-allele mutation.Firstly,three step deafness gene sequencing was adopted in this work,i.e.,the first step was"SLC26A4 gene whole exons and splice sites"sequencing;the second step was"SLC26A4 gene promoter,FOXI1 gene and KCNJ10 gene whole exons"sequencing;and the third step was detection for"SLC26A4 gene copy number variation".Secondly,we collected the results of newborn hearing screening for all patients with the second mutation found in the three step test,and conducted audiological examinations,such as acoustic immittance,auditory brainstem response and auditory steady state response.Thirdly,for novel/VUS mutations,we searched the international deafness gene database or software,such as DVD,ClinVar and Mutation Taster,to predict the pathogenicity of mutations according to the ACMG guideline.Lastly,we analyzed the relationship between genotype and phenotype of newborns with SLC26A4 single allele mutation.Results Among 850 cases,the median age of diagnosis was 4 months.In the first step,850 cases were sequenced.A total of 32 cases(3.76%,32/850)of a second variants were detected,including 18 cases(2.12%,18/850)with identified pathogenic variants;832 cases were sequenced and 8 cases of KCNJ10 gene missense variants were detected among the second step.No missense mutations in the FOXI1 gene and abnormal SLC26A4 gene promoter were detected;the third step sequencing results were all negative.Genotypes and hearing phenotypes included 18 cases combined with the second clear pathogenic variant,16 cases(16/18)referred newborn hearing screening and 2 cases(2/18)passed in both ears;degree of hearing loss consisted of 18

关 键 词：听力损失程度 听力学检查 突变位点 医学遗传学 听性脑干反应 遗传咨询 基因诊断 拷贝数变异 

分 类 号：R764.43[医药卫生—耳鼻咽喉科]