中国荷斯坦奶牛BLF基因5′侧翼区PCR-SSCP多态性及其与乳房炎的相关性分析

Association of BLF 5′-region polymorphisms with mastitis in Chinese Holstein

采用PCR-SSCP技术,对中国荷斯坦奶牛乳铁蛋白基因(Bovine lactoferrin,BLF)5′侧翼区的多态性进行了分析,并用最小二乘法拟合线性模型分析各种基因型与奶牛乳房炎的相关性。结果发现,中国荷斯坦奶牛BLF基因5′侧翼区存在AA、BB和AB 3种基因型,其基因型频率分别为0.8805,0.0299和0.0896;AA基因型在-148位缺失G;与AA基因型相比,BB基因型在-149位发生C→T变异,-135位发生G→A变异;BLF基因5′侧翼区的χ2值为7.992 4(P<0.01),说明BLF基因5′侧翼区的突变处于Hardy-Weinberg非平衡状态,样本群体中AA基因型的SCSLAW最大,BB基因型的SCSLAW最小,两者差异极显著(P<0.01)。表明BLF基因5′侧翼区BB基因型可能与乳房炎的抗性有关,AA基因型可能与乳房炎的易感性有关。

To detect DNA variation of bovine lactoferrin gene,the sequence of 5′-regulatory region was studied by PCR-SSCP.Correlations between all genotypes with the mastitis were analyzed in this study.The results showed three genotypes of BLF 5′allele were observed in Chinese Holstein,genotype AA,genotype BB and genotype AB,and the genotype frequency were 0.880 5,0.029 9 and 0.089 6,respectively.After sequencing,G deletion at-148 was found under the AA genotype,and C→T and G→A transitions were identified under the BB genotype in comparison to the AA genotype.χ^2 test indicated that 5′-regulatory region did not fit Hardy-Weinberg equilibrium（χ^2=7.992 4）（P〈0.01）,The SCSLAW of genotype AA was biggest in the sample colony,and the smallest one was genotype BB,so there was greatly significant difference（P〈0.01） between these two genotypes,which showed that BLF 5′-BB genotype might relate to the resistance of mastitis,and AA genotypes might relate to the susceptibility of mastitis（P〈0.01）.