原发性肉碱缺乏症一个家系的胚胎植入前遗传学检测  

Preimplantation genetic testing for a Chinese pedigree affected with Primary carnitine deficiency

作　　者：邓杰 周知 周多 黄仁良 郭敏 周俏苗 Deng Jie;Zhou Zhi;Zhou Duo;Huang Renliang;Guo Min;Zhou Qiaomiao(Department of Genetics and Prenatal Diagnosis,Hainan Women and Children′s Medical Center,Haikou,Hainan 570206,China;Reproductive Medical Center,Hainan Women and Children′s Medical Center,Haikou,Hainan 570206,China)

机构地区：[1]海南省妇女儿童医学中心医学遗传与产前诊断科,海口570206 [2]海南省妇女儿童医学中心生殖医学中心,海口570206

出　　处：《中华医学遗传学杂志》2024年第12期1483-1490,共8页Chinese Journal of Medical Genetics

基　　金：海南省重大科技计划项目(ZDKJ2021037);海南省优秀人才团队(琼人才办通(2021)21号)。

摘　　要：目的探讨1个原发性肉碱缺乏症(PCD)家系的单基因病胚胎植入前遗传学检测(PGT-M)结果。方法选取2023年4月因"子代(先证者)基因检测发现SLC22A5基因变异、备二胎"就诊于海南省妇女儿童医学中心的1个PCD家系为研究对象。参考美国医学遗传学与基因组学学会(ACMG)制定的《遗传变异分类标准与指南》,判断先证者变异位点致病性。采用Sanger测序法对该家系中先证者及其父母的SLC22A5基因变异位点进行验证,并采用单核苷酸多态性微阵列(SNP-array)方法,构建家系单核苷酸多态性(SNP)单体型,判断致病基因携带情况。先证者父母采取辅助生殖技术受精后,对其活检的囊胚滋养层细胞进行单细胞全基因组扩增(WGA),并采用Sanger测序、二代测序(NGS)和SNP-array等技术,检测胚胎携带SLC22A5基因变异和染色体拷贝数变异(CNV)情况,选取未检测到变异的胚胎进行移植。先证者母亲再次妊娠成功后,因反复阴道出血未进行羊水穿刺产前诊断,于分娩后采集新生儿血样验证PGT-M结果,并进行随访。本研究通过了海南省妇女儿童医学中心医学伦理委员会审查(批准号:HNWCMC伦审2022年第[178]号)。结果本研究先证者SLC22A5基因c.338G>A和c.760C>T变异均被评为致病性变异。PCD先证者家系Sanger测序结果显示,先证者SLC22A5基因c.338G>A和c.760C>T变异分别遗传自其父亲与母亲。成功构建SLC22A5基因c.338G>A和c.760C>T变异位点的单体型。PGT-M结果提示,活检的8枚囊胚中,2枚囊胚WGA失败,其余6枚囊胚的CNV检测结果均为整倍体,其中2枚囊胚SLC22A5基因未检测到变异,3枚SLC22A5基因携带父源或母源单个杂合变异,1枚SLC22A5基因携带父源和母源复合杂合变异。结合胚胎形态学评分,顺利移植1枚CNV未见异常且未携带父源和母源SLC22A5基因变异的最优胚胎后,获宫内单胎妊娠,于38+3孕周活产一健康女婴,婴儿外周血染色体核型分析、CNV检测ObjectiveTo investigate the results of preimplantation genetic testing for monogenic diseases(PGT-M)in a Chinese pedigree affected with Primary carnitine deficiency(PCD).MethodsA pedigree affected with PCD who visited Hainan Women and Children′s Medical Center in April 2023 due to"SLC22A5 gene mutation found in offspring genetic testing and preparing for a second child"was selected as the study subject.The pathogenicity of the proband′s variant sites was determined by referring to the Standards and Guidelines for the Interpretation of Sequence Variants established by the American College of Medical Genetics and Genomics(ACMG).Sanger sequencing was used to verify the variant sites of SLC22A5 gene in the proband and her parents,and the single nucleotide polymorphism(SNP)haplotype of the family was constructed by SNP microarray(SNP array)method to determine the carryer status of pathogenic genes.After fertilization via assisted reproductive technology,whole genome amplification(WGA)was performed on the biopsied trophoblastic cells.Sanger sequencing,next-generation sequencing(NGS),and SNP array techniques were then used to detect variants in the SLC22A5 gene and chromosomal copy number variation(CNV)in the embryos.Embryos without variant were selected for transferring.After the successful pregnancy of the proband′s mother,amniocentesis was not performed for prenatal diagnosis due to repeated vaginal bleeding.After delivery,neonatal peripheral blood sample was collected to verify the results of PGT-M,and follow-up was conducted.This study was reviewed and approved by the Medical Ethics Committee of Hainan Women and Children′s Medical Center(Ethics No.HNWCMC-2022-178).ResultsIn this study,the c.338G>A and c.760C>T variants in the SLC22A5 gene were evaluated as pathogenic variants.Sanger sequencing results of this family showed that c.338G>A and c.760C>T variants in the SLC22A5 gene of the proband were inherited from his father and mother,respectively.The haplotypes of c.338G>A and c.760C>T variants of SLC22A5 g

关 键 词：原发性肉碱缺乏症 SLC22A5基因 植入前诊断 单基因病 胚胎植入前遗传学检测 DNA拷贝数变异 单核苷酸多态性 

分 类 号：R714.8[医药卫生—妇产科学]