3个Stargardt家系ABCA4基因致病突变位点的筛查及验证
Screening and verification of pathogenic mutations on ABCA4 gene in 3 Chinese families with Stargardt disease

目的:对河南省Stargardt病(STGD)家系进行ABCA4基因突变位点分析。方法:收集3个家系12名成员外周静脉血,分别对先证者样本提取基因组DNA,构建基因组文库,捕获、富集主要致病基因ABCA4的外显子及相邻内含子区域,行高通量测序,与数据库比对,定位出疑似变异,最后与家系其他成员及专业数据库进行对比验证,以确定变异。结果:共检测到5个ABCA4个基因突变,均为复合杂合突变:c.2894A>G(p.N965S),为错义突变; c.101_106del(p.34_36del),为缺失突变; c.5899-2A>G,为剪切突变; c.1222C>T(p.R408X),为无义突变; c.1982T>G(p.L661R),为错义突变。所有突变都在其父母一方对应位点存在杂合变异。c.5899-2A>G、c.1222C>T、c.1982T>G 和 c.101_106del为检测到的ABCA4基因新发突变。结论:检测到4个ABCA4基因新发突变,扩增了STGD ABCA4基因突变谱。
Aim: To identify virulence mutation locus on ABCA4 gene in 3 Chinese families with Stargardt disease in Henan Province.Methods: Peripheral venous blood of 12 members from 3 families was collected. Genome DNA was extracted from samples of propositi to establish genomic library, and exon and adjacent intron region of main disease-causing gene ABCA4 were acquired and enriched, high-throughput sequencing and database comparison were carried out to locate suspected mutation. Finally, mutation was confirmed by comparing with other members of the family and professional database.Results: Five mutations were detected, and all were compound heterozygous mutation in ABCA4 gene. c.2894A>G(p.N965S)was a missense mutation, c.101_106del(p.34_36del)was a deletion mutation,c.5899-2A>G was a splicing mutation,c.1222C>T(p.R408X)was a nonsense mutation,c.1982T>G(p.L661R)was a missense mutation. All mutations had heterozygous variation in the corresponding locus of the patients' parents. c.5899-2A>G,c.1222C>T,c.1982T>G and c.101_106del were the novel pathogenic mutations on BACA4 gene.Conclusion: Some new pathogenic mutations on ABCA4 gene related with STGD are found, so ABCA4 mutation spectrum are amplified