Bekele R, Taye M, Abebe G, Meseret S
School of Animal and Range Sciences, College of Agriculture, Hawassa University, P.O. Box 5, Hawassa, Ethiopia.
Department of Animal Science, College of Agriculture and Natural Resource Sciences, Debre Berhan University, P.O. Box 445, Debre Berhan, Ethiopia.
Int J Genomics. 2023 Jul 27;2023:8497453. doi: 10.1155/2023/8497453. eCollection 2023.
Genome-wide association studies (GWAS) are a powerful tool for identifying genomic regions and causative genes associated with economically important traits in dairy cattle, particularly complex traits, such as milk production. This is possible due to advances in next-generation sequencing technology. This review summarized information on identified candidate genes and genomic regions associated with milk production traits in Holstein and its crossbreds from various regions of the world. Milk production traits are important in dairy cattle breeding programs because of their direct economic impact on the industry and their close relationship with nutritional requirements. GWAS has been used in a large number of studies to identify genomic regions and candidate genes associated with milk production traits in dairy cattle. Many genomic regions and candidate genes have already been identified in Holstein and its crossbreds. Genes and single nucleotide polymorphisms (SNPs) that significantly affect milk yield (MY) were found in all autosomal chromosomes except chromosomes 27 and 29. Half of the reported SNPs associated with fat yield and fat percentage were found on chromosome 14. However, a large number of significant SNPs for protein yield (PY) and protein percentage were found on chromosomes 1, 5, and 20. Approximately 155 SNPs with significant influence on multiple milk production traits have been identified. Several promising candidate genes, including diacylglycerol O-acyltransferase 1, plectin, Rho GTPase activating protein 39, protein phosphatase 1 regulatory subunit 16A, and sphingomyelin phosphodiesterase 5 were found to have pleiotropic effects on all five milk production traits. Thus, to improve milk production traits it is of practical relevance to focus on significant SNPs and pleiotropic genes frequently found to affect multiple milk production traits.
全基因组关联研究（GWAS）是一种强大的工具，可用于识别与奶牛经济重要性状相关的基因组区域和致病基因，特别是复杂性状，如产奶量。由于下一代测序技术的进步，这才成为可能。本综述总结了有关世界各地荷斯坦奶牛及其杂交品种中已鉴定的与产奶性状相关的候选基因和基因组区域的信息。产奶性状在奶牛育种计划中很重要，因为它们对该行业有直接经济影响，并且与营养需求密切相关。GWAS已在大量研究中用于识别与奶牛产奶性状相关的基因组区域和候选基因。在荷斯坦奶牛及其杂交品种中已经鉴定出许多基因组区域和候选基因。除27号和29号染色体外，在所有常染色体上都发现了对产奶量（MY）有显著影响的基因和单核苷酸多态性（SNP）。报告的与乳脂产量和乳脂率相关的SNP中有一半位于14号染色体上。然而，在1号、5号和20号染色体上发现了大量与乳蛋白产量（PY）和乳蛋白率相关的显著SNP。已经鉴定出大约155个对多种产奶性状有显著影响的SNP。几个有前景的候选基因，包括二酰基甘油O-酰基转移酶1、网蛋白、Rho GTP酶激活蛋白39、蛋白磷酸酶1调节亚基16A和鞘磷脂磷酸二酯酶5，被发现对所有五个产奶性状都有多效性影响。因此，为了改善产奶性状，关注经常发现影响多种产奶性状的显著SNP和多效性基因具有实际意义。
