【摘要】 目的探讨二代测序(NGS)在Meckel综合征植入前遗传学检测(PGT)的应用价值和优势。方法选取1例Meckel综合征家系,通过Sanger测序调查家系成员MKS1基因突变情况。以MKS1基因编码区为目标区域,在该基因上下游2M区域内选择200个单核苷酸多态位点(SNP)作为遗传连锁标记,多重PCR和NGS后选择有效SNP位点构建家系成员SNP单倍型,确定携带MKS1基因突变的风险染色体。采用NGS对胚胎MKS1基因突变位点直接测序和构建胚胎SNP单倍型进行PGT。对未检测到突变和杂合携带的胚胎进行了低深度的染色体非整倍性筛查。结果采用NGS对胚胎基因突变位点直接测序和构建SNP单倍型结果显示活检的6个胚胎中3个未检测到突变,2个杂合携带,1个致病。5个未检测到突变和杂合携带胚胎染色体非整倍体筛查结果显示其中4个为平衡的整倍体胚胎。结论应用NGS对Meckel综合征家系进行PGT,可以阻断此单基因病在该家系中的再发风险,还可以避免选择非整倍体胚胎而导致的流产问题。更多还原

【Abstract】 Objective To explore the application value and advantage of next generation sequencing(NGS)in preimplantation genetic testing(PGT)of Meckel syndrome. Methods A family with Meckel syndrome was selected,and the mutation of MKS1 gene in family members was investigated by Sanger sequencing. The coding region of MKS1 gene was selected as the target region,and 200 single nucleotide polymorphisms(SNPs)were selected as the genetic linkage markers in the upstream and downstream 2 M regions of the gene. After multiple PCR and NGS,the effective SNPs were selected to construct SNP haplotypes of family members and risk chromosomes carrying mutations in MKS1 gene were identified. Direct sequencing of MKS1 gene mutations in embryos and construction of SNP haplotypes of embryo by NGS were used for PGT.Low-depth chromosome aneuploidy screening was carried out in the embryos without mutation and heterozygosity. Results Using NGS to directly sequence the genetic mutation sites of embryos and construct SNP haplotypes,the results showed that 3 of the 6 embryos biopsied had no mutations,2 were heterozygous carriers,and 1 was pathogenic. The screening results of chromosomal aneuploidy of 5 undetected mutant and heterozygous embryos showed that 4 of them were balanced euploid embryos. Conclusion Applying NGS to PGT in a family with Meckel syndrome can block the risk of recurrence of this monogenic disease in the family,and can also avoid the problem of miscarriage caused by the selection of aneuploid embryos.更多还原