中国荷斯坦奶牛RPL23A、ACACB基因3个SNPs检测及其与产奶性状的关联分析

旨在开展奶牛群体高乳成分功能基因的验证与筛选，利用微流控芯片自主选育技术分析北京地区母牛群体高乳蛋白、高乳脂基因频率，同时分析基因多态性及其与产奶性状的相关性。本研究对北京地区8个大型奶牛场1 596头中国荷斯坦奶牛RPL23A、ACACB基因的多态性进行了检测，所有个体均为3胎以内的泌乳牛，收集每头牛所有测定日的产奶量、乳脂率、乳蛋白率等数据，同时对3个多态位点不同基因型与产奶性状进行了关联分析。RPL23A基因的SNP位点g.20146771G>A，在第一泌乳期，与产奶量、乳脂量、乳脂率和乳蛋白量均达到极显著关联（P<0.01），第二泌乳期，g.20146771G>A与5个产奶性状均呈极显著关联（P<0.01）。ACACB基因的SNP位点g.63962768C>T，在第一泌乳期，与产奶量、乳脂量、乳脂率和乳蛋白量均呈极显著关联（P<0.01），在第二泌乳期，与产奶量、乳脂量、乳脂率和乳蛋白率呈极显著关联（P<0.01）。结果表明，RPL23A、ACACB基因可以作为影响中国荷斯坦奶牛产奶性状的候选基因用于标记辅助选择，以上基因位点可能通过直接或间接的途径影响奶牛的乳脂或乳蛋白性状，对产奶性状起到重要调控作用。本研究为荷斯坦奶牛后续的标记辅助选择奠定了良好基础。

Detection of 3 SNPs of RPL23A,ACACB Genes and Their Association with Milk Production Traits in Chinese Holstein Cows

The purpose of the experiment was to carry out the verification and screening of functional genes affecting high milk composition in dairy cattle. The gene frequencies of high milk protein and high milk fat in cow populations in Beijing were analyzed by using microfluidic chip independent breeding technology, and the genetic polymorphism and its correlation with milk production traits were analyzed. In this study, the polymorphism of RPL23A and ACACB genes in 1 596 Chinese Holstein cows from 8 Beijing large dairy farms was detected,all individuals were lactating cows with less than 3 fetuses. The data of milk yield, milk fat rate and milk protein rate of each cow were collected. At the same time, the association between different genotypes of 3 polymorphic loci and milk production traits was analyzed. The SNP locus of RPL23A gene g.20146771G>A was significantly correlated with milk yield, milk fat content, milk fat rate and milk protein content in the first lactation period (P<0.01), and g.20146771G>A was significantly associated with 5 milk production traits in the second lactation period (P<0.01). The SNP locus g.63962768 C>T of ACACB gene was significantly correlated with milk yield, milk fat content, milk fat rate and milk protein content in the first lactation period (P<0.01), and it was significantly associated with milk yield, milk fat content, milk fat rate and milk protein rate in the second lactation period (P<0.01). This results showed that RPL23A and ACACB genes can be used as candidate genes for marker assisted selection to affecting milk production traits of Chinese Holstein cows. The above gene loci may directly or indirectly affect milk fat or milk protein traits of cows, and play an important role in regulating milk production traits. This study laid a good foundation for the subsequent marker assisted selection of Holstein cattle.