应用Amp-RFLP和SSCP技术分析DNaseⅠ基因的C1978G基因座多态性

为研究人类DNaseⅠ基因点突变C1978G多态性,应用Amp－RFLP和SSCP技术对DNaseⅠ基因C1978G基因座分型,调查173例汉族无关个体,获DNaseⅠ*1978C和*1978G基因频率,即分别为0．5058和0．4942。其基因型频率分布与Hardy-Weinberg平衡吻合,基因座杂合度0．5028,Dp值0．6040,PE值0．1875。经对Iida等介绍的方法作了改良,分型结果稳定可靠,电泳分离时间由18h减至6h。研究证实,DNaseⅠ基因C1978G点突变是一个高多态性基因座,可应用于法医材料的分型调查。     

片形吸虫第一内转录间隔区DNA多态性的研究

以不同地区的片形吸虫虫株为研究对象 ,经PCR扩增出了ITS 1部分基因片段 ,采用单链构象多态性 (SSCP)方法 ,并结合序列分析研究了不同地区片形吸虫ITS 1DNA的多态性。不同地区的样品经SSCP分析 ,显示 3种带型 ,第 1种为大片形吸虫的带型 ,第 2种为肝片形吸虫的带型 ,第 3种为 2种带形的混合带型。广西区样品和大部分贵州省样品属于大片形吸虫带型 ;四川省、黑龙江省和部分贵州省样品为混合带型 ;南京市和甘肃省样品为肝片形吸虫带型或混合带型。测序结果表明 ,根据ITS 1基因的序列变异位点可区分 2种片形吸虫 ;表现为混合带型的样品在变异位点具有多态性。本研究结果显示 ,ITS 1片段可作为遗传标记用以区分大片形吸虫和肝片形吸虫 ,同时也证实 ,在我国除了这 2种片形吸虫外 ,还可能存在着“中间型”的片形吸虫     

中国荷斯坦乳牛DRB3基因多态性的PCR-SSCP分析及其与泌乳性状的相关性

采用PCR-SSCP技术,对中国荷斯坦乳牛DRB3基因的多态性进行了分析,并用线性数学模型分析了各种基因型与乳牛乳腺炎的相关性.结果显示,DRB3基因有AA、BB和AB 3种基因型,其基因型频率分别为0.46,0.33和0.21;DRB3基因多态的产生是第88位产生A→T突变、第118位产生T→A突变以及第165位产生A→G的替换造成的;基因型频率分布的X2值为19.56(P＜0.01),DRB3基因的突变处于Hardy-Weinberg非平衡状态.相关性分析表明,不同基因型乳牛之间泌乳性状的差异不显著.     

Sequence analysis of STR polymorphisms at locus ACTBP2 in the Taiwanese population

A highly polymorphic sequence structure is reported in the human beta-actin related pseudogene 2 (ACTBP2) (SE33) locus in members of the Taiwanese Han population. A total of 100 unrelated members of the Taiwanese Han population were used in the study. Alleles that shared the same size but differ in their sequence are described to allow for inter laboratory sharing of data. PCR products amplified from this locus were separated by single-strand conformation polymorphism electrophoresis, the single-stranded DNA bands were excised from the gels, a second amplification performed, and then the PCR products were sequenced. All the alleles differed by either 2 or 4 bp. Sequence variations were observed as deletions or insertions in the repeat units AG (or AA) and AAAG. Additionally, transitions in the flanking regions were recorded. A total of 27 alleles with 71 associated genotypes were recorded if the alleles were defined by size, but 68 alleles with 88 associated genotypes were noted with the alleles were scored on the basis of sequence variation. The power of discrimination (Pd) of this single locus was 0.9874 making the human ACTBP2 a good alternative marker for individual identification and paternity testing.