Cho Kwang-Hyun, Oh Jae-Don, Kim Hee-Bal, Park Kyung-Do, Lee Joon-Ho
Animal Genomics and Breeding Center, Hankyong National University, Anseong 456-749, Korea .
Department of Agricultural Biotechnology, Seoul National University, Seoul 151-921, Korea .
Asian-Australas J Anim Sci. 2015 Mar;28(3):328-33. doi: 10.5713/ajas.14.0337.
A genome wide association study was conducted using estimated breeding value (EBV) for milk production traits from 1st to 4th lactation. Significant single nucleotide polymorphism (SNP) markers were selected for each trait and the differences were compared by lactation. DNA samples were taken from 456 animals with EBV which are Holstein proven bulls whose semen is being sold or the daughters of old proven bulls whose semen is no longer being sold in Korea. High density genome wide SNP genotype was investigated and the significance of markers associated with traits was tested using the breeding value estimated by a multiple lactation model as a dependent variant. As the result of significance comparisons by lactations, several differences were found between the first lactation and subsequent lactations (from second to 4th lactation). A similar trend was noted in mean deviation and correlation of the estimated effects by lactation. Since there was a difference in the genes associated with EBV for each trait between first and subsequent lactations, a multi-lactation model in which lactation is considered as a different trait is genetically useful. Also, significant markers in all lactations and common markers for different traits were detected, which can be used as markers for quantitative trait loci exploration and marker assisted selection in milk production traits.
利用第1至第4泌乳期产奶性状的估计育种值（EBV）进行了全基因组关联研究。为每个性状选择了显著的单核苷酸多态性（SNP）标记，并按泌乳期比较差异。DNA样本取自456头具有EBV的动物，这些动物是韩国正在销售精液的荷斯坦种公牛或不再销售精液的老种公牛的女儿。研究了高密度全基因组SNP基因型，并使用多泌乳模型估计的育种值作为相关变量来检验与性状相关标记的显著性。作为按泌乳期进行显著性比较的结果，在第一泌乳期和随后的泌乳期（从第二到第四泌乳期）之间发现了一些差异。在泌乳期估计效应的平均偏差和相关性方面也注意到了类似趋势。由于第一泌乳期和随后泌乳期之间与每个性状的EBV相关的基因存在差异，将泌乳视为不同性状的多泌乳模型在遗传学上是有用的。此外，还检测到了所有泌乳期的显著标记和不同性状的共同标记，这些标记可用于产奶性状的数量性状位点探索和标记辅助选择。
