Rocha J L, Sanders J O, Cherbonnier D M, Lawlor T J, Taylor J F
Department of Animal Science, Texas A&M University, College Station 77843, USA.
J Dairy Sci. 1998 Jun;81(6):1663-80. doi: 10.3168/jds.S0022-0302(98)75734-0.
This study addresses the utility of 11 blood groups as selection aids in Holstein breeding schemes and considers issues inherent to the approach of resolving quantitative variation into components that are due to quantitative trait loci. The data consisted of predicted transmitting abilities of 22,614 bulls, first lactation information on 1,924,171 cows, and type scores on 447,800 cows. Linear models were fitted under male half-sib designs, female half-sib designs, and granddaughter designs as well as under the assumption of direct effects of the markers. The evolution of allele frequencies through time was determined, and previous research results were synthesized according to criteria of consistency of biological significance. The inconsistency of results across studies and analytical designs alludes to the importance of the intrinsic nonadditivity of genetic and biological phenomena to quantitative trait locus detection and marker-assisted selection. In our analyses, three associations met the criteria of consistency--a C blood group effect on rump angle, an L effect on milk yield and composition traits, and an S effect on milk fat yield. The M locus appears to be directly associated with effects on milk and protein yields. An enhanced understanding of the biochemical and physiological bases of quantitative genetics should be a long-term objective of this type of genetic analysis.
本研究探讨了11种血型在荷斯坦奶牛育种方案中作为选择辅助工具的效用，并考虑了将数量变异分解为归因于数量性状基因座的组成部分这一方法所固有的问题。数据包括22614头公牛的预测传递能力、1924171头母牛的头胎泌乳信息以及447800头母牛的体型评分。在线性模型中，拟合了雄性半同胞设计、雌性半同胞设计和孙女设计，以及标记直接效应的假设。确定了等位基因频率随时间的演变，并根据生物学意义一致性标准综合了先前的研究结果。各项研究和分析设计结果的不一致表明，遗传和生物学现象的内在非加性对数量性状基因座检测和标记辅助选择具有重要意义。在我们的分析中，有三个关联符合一致性标准——C血型对臀角的影响、L对产奶量和成分性状的影响，以及S对乳脂产量的影响。M基因座似乎与对产奶量和蛋白质产量的影响直接相关。深入理解数量遗传学的生化和生理基础应该是这类遗传分析的一个长期目标。
