DHPLC联合一代测序技术在脊髓肌萎缩症携带者筛查中的应用  

The application of DHPLC combined with first-generation sequencing technique in screening the carriers of spinal muscular atrophy

作　　者：刘春苗 孟雁欣 张志敏[1] 杨扬 王亚男[1] 张海娟[1] LIU Chunmiao;MENG Yanxin;ZHANG Zhimin(Department of Obstetrics,The Fourth Hospotal of Shijiazhuang,Hebei,Shiijiazhuang 050011,China;不详)

机构地区：[1]河北省石家庄市第四医院产科,050011 [2]河北省石家庄市第四医院产前诊断中心,050011

出　　处：《河北医药》2022年第4期504-507,共4页Hebei Medical Journal

基　　金：河北省青年自然科学基金项目(编号:H2017106030);石家庄市科学技术研究与发展计划项目(编号:211461163)。

摘　　要：目的探讨高效液相色谱联合一代测序技术进行运动神经元生存基因(survival motor neuron,SMN)缺失/点突变检测在脊髓肌萎缩症(spinal muscular atrophy,SMA)携带者筛查中的临床应用价值。方法收集2018年1月至2019年1月就诊的3544例样本进行高效液相色谱技术(DHPLC)检测,一代测序技术序惯性行SMN1点突变测序分析。结果3544例样本共检出61例拷贝异常携带者(男33例,女28例),检出率1.72%。42例SMN1缺失携带(约占1.18%),31例SMN1∶SMN2为1∶1,11例SMN1∶SMN2为1∶2。17例SMN1转换成SMN2(SMN1∶SMN2=1∶3),约占0.48%。2例SMN1∶SMN2=1∶0。61例SMA携带者配偶行SMN1检测,11例SMN1变异。9例SMN1缺失携带者SMN1∶SMN2=1∶1,2例SMN1转换成SMN2(SMN1∶SMN2=1∶3)。3544例样本行SMN1靶向测序,2例为SMN1点突变携带者,1例p.Q164X为致病突变携带者,1例为5号内含子位置SNP位点。对上述配偶进行SMN1拷贝缺失及点突变检测未见异常。余样本未见明确变异位点。妇双方知情同意并签署知情同意书后,11对夫妇双方均为SMN1携带者胎儿于孕18周进行胎儿羊水染色体检查。测得2例胎儿SMN1纯合缺失,即SMA患者,1例胎儿缺失变异携带者SMN1∶SMN2=1∶1,1例胎儿为SMN1(p.Q164X)变异点突变携带者。余未见异常。对11例高危胎儿随访,2例SMN1纯合缺失胎儿夫妇选择双方终止妊娠。对不同携带者SMN1∶SMN2比值以SMN1∶SMN2=1∶1最为常见,与其他类型携带者比较有统计学意义(P<0.05)。结论研究检出SMA携带者中以SMN1∶SMN2为1∶1最为常见,提示不同地区及种族人群携带者基因型存在差异;规范、精准SMA携带筛查流程建立可有效降低缺陷患儿出生,也是实现SMA二级预防的有效途径;HPLC联合单基因测序技术可提高SMA分子检测阳性率。Objective To investigate the clinical value of detecting the deletion/point mutation of survival motor neuron(SMN1)in prenatal screening of spinal muscular atrophy(SMA)by high performance liquid chromatography(DHPLC)combined with first-generation sequencing.Methods A total of 3,544 specimens colleted from prenatal diagnostic center of our from January 2018 to January 2019 were enrolled in the study,which were detected by(DHPLC).The DHPLC point mutation was further analyzed by SMN1 sequencing.Results Of the 3544 specimens,61 copy abnormal carriers(28 females and 33 males)were detected,with detection rate being 1.72%.In 42 SMN1 deletion carriers(about 1.18%),the ratio of SMN1∶SMN2 was 1∶1 in 11 cases,and the ratio of SMN1∶SMN2 was 1∶2 in 31 cases.Seventeen cases of SMN1 were transformed into SMN2(SMN1∶SMN2=1∶3),accounting for about 0.48%.And 2 cases of SMN1∶SMN2=1∶0.The spouses of 61 SMA carriers were tested for SMN1,and 11 of them had SMN1 mutation.In 9 SMN1 deletion carriers,SMN1∶SMN2=1∶1,and 2 SMN1 transformed into SMN2(SMN1∶SMN2=1∶3).SMN1 targeting sequencing was performed on 3544 specimens,in which,there were 2 carriers of SMN1 point mutation,1 carrier of pathogenic mutation P.Q164X,and 1 case of SNP site of intron 5.SMN1 copy deletion and point mutation,and no abnormalities were found.No specific mutation loci were found in the other 3542 specimens.After the informed consent of both couples and the signing of the informed consent,the fetuses carrying SMN1 in 11 couples were examined at 18 weeks of gestation for fetal amniotic fluid chromosome,of whom,two fetuses with homozygous deletion of SMN1(SMA patients),1 fetus with deletion mutation of SMN1∶SMN2=1∶1,and 1 fetus with SMN1(p.Q164X)mutation point mutation.Moreover 11 high-risk fetuses were followed up,and 2 fetuses with homozygous deletion of SMN1 chose to terminate pregnancy by both parties.And SMN1∶SMN2 ratio was the most common among different carriers,which was statistically significant,as compared with other carriers.Conc

关 键 词：脊髓肌萎缩症 产前诊断 携带者 单基因分析 DHPLC 

分 类 号：R746.4[医药卫生—神经病学与精神病学]