Mkize Nelisiwe, Maiwashe Azwihangwisi, Dzama Kennedy, Dube Bekezela, Mapholi Ntanganedzeni
Agricultural Research Council-Animal Production Campus, Private Bag X2, Irene 0062, South Africa.
Department of Animal Sciences, University of Stellenbosch, Private Bag X1, Matieland, Stellenbosch 7602, South Africa.
Pathogens. 2021 Dec 9;10(12):1604. doi: 10.3390/pathogens10121604.
Understanding the biological mechanisms underlying tick resistance in cattle holds the potential to facilitate genetic improvement through selective breeding. Genome wide association studies (GWAS) are popular in research on unraveling genetic determinants underlying complex traits such as tick resistance. To date, various studies have been published on single nucleotide polymorphisms (SNPs) associated with tick resistance in cattle. The discovery of SNPs related to tick resistance has led to the mapping of associated candidate genes. Despite the success of these studies, information on genetic determinants associated with tick resistance in cattle is still limited. This warrants the need for more studies to be conducted. In Africa, the cost of genotyping is still relatively expensive; thus, conducting GWAS is a challenge, as the minimum number of animals recommended cannot be genotyped. These population size and genotype cost challenges may be overcome through the establishment of collaborations. Thus, the current review discusses GWAS as a tool to uncover SNPs associated with tick resistance, by focusing on the study design, association analysis, factors influencing the success of GWAS, and the progress on cattle tick resistance studies.
了解牛蜱抗性的生物学机制，有助于通过选择性育种促进遗传改良。全基因组关联研究（GWAS）在揭示蜱抗性等复杂性状的遗传决定因素的研究中很受欢迎。迄今为止，已经发表了各种关于牛蜱抗性相关单核苷酸多态性（SNP）的研究。与蜱抗性相关的SNP的发现，已导致相关候选基因的定位。尽管这些研究取得了成功，但与牛蜱抗性相关的遗传决定因素的信息仍然有限。这就需要进行更多的研究。在非洲，基因分型的成本仍然相对较高；因此，进行GWAS是一项挑战，因为推荐的动物最小数量无法进行基因分型。这些种群规模和基因型成本挑战可以通过建立合作来克服。因此，本综述通过关注研究设计、关联分析、影响GWAS成功的因素以及牛蜱抗性研究的进展，讨论了GWAS作为一种揭示与蜱抗性相关SNP的工具。
