ROH及其在绵羊遗传育种中的应用研究进展

Research Progress of ROH and Its Application in Sheep Genetic Breeding

连续性纯合片段(runs of homozygosity,ROH)是基因组中的一段长纯合片段,不同长度的ROH和个体与共同祖先的亲缘背景相关联,亲缘关系越远ROH片段越短。在近交过程中,随着世代数的增加,子代个体从共同祖先遗传得到的ROH会被不断地打断重排。在整个遗传信息传递过程中,可以根据ROH的长短来判断个体间亲缘关系的亲近程度。ROH受种群近交、种群瓶颈、基因组特征、人工选择等多种因素的制约,这些制约因素会在其基因组上留下各种印记。ROH中有丰富的遗传信息,促使ROH成为研究绵羊基因组信息的新手段。近年来,随着高通量测序技术的发展,研究人员利用基因组ROH来评估近交程度和遗传多样性、推断种群结构和种群历史、筛选和鉴定重要经济性状功能基因,进行个体选择并追踪选择信号。因此,笔者就ROH产生原理、影响因素、检测方法及其在绵羊遗传育种中的应用等方面进行综述,以期能准确制定绵羊种质资源保护策略,为ROH在绵羊遗传育种中的应用提供理论依据。

Runs of homozygosity(ROH)is a long homozygosity segment in the genome.ROH of different lengths and individuals are associated with the genetic background of a common ancestor,and the farther of genetic relationship has the shorter ROH fragment.In the process of inbreeding,with the increase of the number of generations,the ROH inherited from the common ancestor of the offspring individuals will be constantly interrupted and rearranged.ROH is subject to a variety of factors such as population inbreeding,population bottleneck,genomic characteristics and artificial selection,etc.,which will leave various imprints on its genome.There is abundant genetic information in ROH fragments,which equip a new tool for studying sheep genome information.In recent years,with the development of high-throughput sequencing technology,researchers use genome ROH to assess inbreeding degrees and population diversity,infer population structure and history,screen and identify important economic trait genes,and carry out individual selection track selection signals.Therefore,the author summarized the generation principle,influencing factors,detection methods and the application of ROH in sheep genetic breeding,so as to accurately formulate the protection strategy of sheep germplasm resources and provide theoretical basis for the application of ROH in sheep genetic breeding.