A genome-wide scan to detect signatures of recent selection in Australian Merino sheep

Domestication and selection are processes that conserve the pattern of genetic diversities between and within populations. Identification of genomic regions that are targets of selection for phenotypic traits is one of the main aims of research in animal genetics. An approach for identifying divergently selected regions of the genome is to compare FST values among loci to estimate the genetic variability between and within populations. In this study, a whole genome scan using the 50K Illumina Ovine SNP chip was performed in seventeen flocks of Australian Merino sheep (8 CRC flocks and 9 SG flocks). Population differentiation using FST in these flocks revealed seven genomic regions. These areas were located on chromosomes 2 (two region), 3, 6, 7, 16 and 26 (Wintheta> 0.15). In this study, a number of candidate genes associated with reproductive and growth traits were identified. Study of the reported QTLs in these regions of the ovine and bovine genomes also showed that they associated with important traits such as reproduction, carcass yield, growth and wool traits. Further validation studies of these regions can be used to identify the candidate genes for economically important traits in sheep breeds. The results also provided intuitions for further understanding of the genetic diversities among the Merino flocks.

Keywords:

Australian Merino sheep , genomic scan , population differentiation , signatures of selection