Identification of genetic markers that affect economically important traits is of high value from a biological point of view, enabling the targeting of candidate genes and providing practical benefits for the industry such as wide-scale genomic selection. This study is one of the first to investigate the genetic background of economically important traits in dairy goats using the caprine 50K single nucleotide polymorphism (SNP) chip. The aim of the project was to perform a genome-wide association study for milk yield and conformation of udder, teat, and feet and legs. A total of 137,235 milk yield records on 4,563 goats each scored for 10 conformation traits were available. Out of these, 2,381 goats were genotyped with the Illumina Caprine 50K BeadChip (Illumina Inc., San Diego, CA). A range of pseudo-phenotypes were used including deregressed breeding values and pseudo-estimated breeding values. Genome-wide association studies were performed using the multi-locus mixed model (MLMM) algorithm implemented in SNP & Variation Suite v7.7.8 (Golden Helix Inc., Bozeman, MT). A genome-wise significant [−log₁₀(P-value) > 5.95] SNP for milk yield was identified on chromosome 19, with additional chromosome-wise significant (−log₁₀(P-value) > 4.46] SNP on chromosomes 4, 8, 14, and 29. Three genome-wise significant SNP for conformation of udder attachment, udder depth, and front legs were identified on chromosome 19, and chromosome-wise SNP were found on chromosomes 4, 5, 6, 10, 11, 12, 13, 14, 15, 16, 17, 18, 21, 23, and 27. The proportion of variance explained by the significant SNP was between 0.4 and 7.0% for milk yield and between 0.1 and 13.8% for conformation traits. This study is the first attempt to identify SNP associated with milk yield and conformation in dairy goats. Two genome-wise significant SNP for milk yield and 3 SNP for conformation of udder attachment, udder depth, and front legs were found. Our results suggest that conformation traits have a polygenic background because, for most of them, we did not identify any quantitative trait loci with major effect.

从生物学的角度出发，鉴定影响经济重要性状的遗传标记具有很高的价值，使靶向候选基因成为可能，并为行业提供了实际的好处，例如大规模的基因组选择。这项研究是第一个使用山羊50K单核苷酸多态性（SNP）芯片研究奶山羊经济重要性状遗传背景的研究之一。该项目的目的是进行全基因组关联研究，以研究牛奶的产量以及乳房，乳头，脚和腿的构型。共有137,235条牛奶记录，记录了4,563只山羊，每种山羊都获得了10种构象性状评分。在其中的2,381只山羊中，使用Illumina Caprine 50K BeadChip（加利福尼亚州圣地亚哥的Illumina Inc.）进行了基因分型。使用了一系列伪表型，包括递减的育种值和伪估计的育种值。使用SNP＆Variation Suite v7.7.8（Golden Helix Inc.，Bozeman，MT）中实现的多基因座混合模型（MLMM）算法进行了全基因组关联研究。基因组意义上的[-log₁₀（P值）> 5.95]在19号染色体上鉴定出牛奶产量的SNP，另外在染色体上显着（-log ₁₀（P（-值）> 4.46]在4、8、14和29号染色体上的SNP。在19号染色体上鉴定出三个基因组意义上显着的乳房附着，乳房深度和前腿构象，并且在19位染色体上发现了染色体SNP。染色体4、5、6、10、11、12、13、14、15、16、17、18、21、23和27。通过有效SNP解释的变异比例在牛奶产量的0.4％和7.0％之间构象特征介于0.1和13.8％之间。这项研究是鉴定与奶山羊产奶量和构象有关的SNP的首次尝试。发现了两个基因组显着的SNP，可提高牛奶产量，并获得3个SNP，用于乳房附着，乳房深度和前腿构象。我们的结果表明，构象性状具有多基因背景，因为对于大多数人而言，