Identifying targets of positive selection in farm animals has, until recently, been frustratingly slow, relying on the analysis of individual candidate genes. Genomics, however, has provided the necessary resources to systematically interrogate the entire genome for signatures of selection. This review described important recent results derived from the application of genome-wide scan to the study of genetic changes in farm animals. These included findings of regions of the genome that showed breed differentiation, evidence of selective sweeps within individual genomes and signatures of demographic events. Particular attention is focused on the study of the implications for domestication. To date, sixteen genome-wide scans for recent or ongoing positive selection have been performed in farm animals. A key challenge is to begin synthesizing these newly constructed maps of selection into a coherent narrative of animal breed evolutionary history and derive a deeper mechanistic understanding of how animal populations improve or evolve. The major insights from the surveyed studies are highlighted and directions for future study are suggested.
本实验旨在研究内蒙古绒山羊背最长肌、臂三头肌和臀肌3个部位骨骼肌差异表达的主要信号通路和关键基因的表达规律,以提高绒山羊基因组的注释水平。以3只在相同饲养背景下的绒山羊成年母羊为研究对象,屠宰后取3个部位骨骼肌肌肉组织并提取总RNA,反转录建立c DNA文库,利用Illumina Mi Seq高通量测序技术,建立了绒山羊3个骨骼肌其mRNA水平上的转录组分析平台。结果得到了18.64 Gb的信息量,92278723对双端reads,发现影响绒山羊骨骼肌生长发育的差异基因多来自轻链肌球蛋白家族、重链肌球蛋白家族。内蒙古绒山羊背最长肌、臂三头肌和臀肌3个部位骨骼肌在转录组水平上存在差异。
