【摘要】 【目的】研究EXT1与EXT2基因在我国南方正常人及致病性突变已明确的遗传性多发性骨软骨瘤病人中的多态性。【方法】选取50例中国南方健康汉族个体及13例致病突变已明确的遗传性多发性骨软骨瘤病人,提取基因组DNA,对包含5’UTR区、编码区、外显子-内含子交界区及3’UTR区的PCR产物进行直接测序。鉴定基因内的遗传变异,并将结果和国际数据库中的数据进行对比。【结果】在所有研究对象中共发现15个不同的EXT1基因的单核苷酸多态性(SNPs):3个在编码区,为同义突变,11个在内含子区,1个在3’UTR区;其中有3个SNPs为数据库未报道的新发现多态位点。22个EXT2基因的SNPs:3个在编码区,也为同义突变,16个在内含子区,3个在3’UTR区;其中有7个SNPs为本研究新发现多态位点。【结论】中国南方汉族人与遗传性多发性骨软骨瘤病人EXT1和EXT2基因的多态性与dbSNP数据库登记资料不完全一致,某些SNPs可能存在种族差异。本研究不仅有利于了解EXT1和EXT2基因结构,也为其多态性与致病性突变的鉴定提供了依据。更多还原

【Abstract】 [Objective]To investigate the polymorphisms of the EXT1 and EXT2 genes in Southern Han Chinese people and in 13 hereditary multiple exostoses(HME) patients whose causal mutations had already been identified.[Methods]Genomic DNA was extracted from 50 healthy unrelated southern Chinese Han individuals and 13 HME patients with known casual mutations in these two genes.PCR products spanning the coding regions,intron-exon boundaries,5’and 3’UTR of the genes were sequenced.Variations identified in the sequences were compared with those retrieved from the databases.[Results] Fifteen genetic variations of EXT1 were identified,of which 3 are synonymous coding variations,11 in intronic region and 1 in 3’UTR.3 of the 15 variations were novel SNPs.Twenty-two variations of EXT2 were detected,3 are synonymous coding variations,16 in intronic region and 3 in 3’UTR.7 of the 22 genetic variations in EXT2 were novel.[Conclusions] Ten novel variations in EXT1 and EXT2 gene have been identified in our study.Twenty-seven variations already in the databases were confirmed.Our results provide useful information for the genetic variations of the two genes among Southern Han Chinese.The results also provide important information for differentiation of causal mutations of EXT1 and EXT2 genes from innocuous polymorphisms.更多还原