Document Type : Research Paper
Authors
1
Ph.D. Candidate, Department of Animal Science, Ramin Agricultural and Natural Resources University, Iran
2
Professor, Department of Animal Science, Ramin Agricultural and Natural Resources University, Iran
3
Assistant Professor, Department of Animal Science, College of Agricultural and Natural Resources, Arak University, Iran
4
Assistant Professor, Department of Animal Science, Aburaihan campus University of Tehran, Iran
5
Research Fellow Centre for Clinical Brain Sciences, University of Edinburgh, UK
Abstract
The detection of genomic regions under positive selection is one of the important topics in population genetics. The objective of the present study was to identify the genomic regions that have been under natural or artificial selection in Afshari and Moghani sheep breeds. Seventy-five samples from Afshari (N=41) and Moghani (N=34) breeds have been genotyped using the Illumina Ovine SNP50K BeadChip. Unbiased method of population differentiation index (Theta) was used to detect the positive selection signatures using Lokern R package. The results of this study revealed 16 genetic regions on chromosomes 2, 3, 4, 8, 9, 13, 15, 22 and 26 where have been under positive selection in these two Iranian sheep breeds. A majority of the genes were involved in signal transduction pathways in a wide variety of cellular and biochemical processes. In particular, selection signatures were identified spanning several genes that directly or indirectly influenced pigmentation (EDN3, BNC2), skeletal morphology and body size (ALX4, EXT2, BMP2), metabolic regulation (PPP1R3D) and immune response (IL2RB). The results of the present study and identified genomic regions suggest that the selection during the evolution and adaptation to the different environments and geographical conditions led to population differentiation in Afshari and Moghani breeds. In conclusion, finding of this study can play an important role in tracing the genomic regions associated with the distinctive traits of these two indigenous breeds.
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