Acta Univ. Agric. Silvic. Mendelianae Brun. 2019, 67, 1165-1170

https://doi.org/10.11118/actaun201967051165
Published online 2019-10-31

Runs of Homozygosity as Footprints of Selection in the Norik of Muran Horse Genome

Nina Moravčíková1, Radovan Kasarda1, Ondrej Kadlečík1, Anna Trakovická1, Marko Halo2, Juraj Candrák1

1Department of Animal Genetics and Breeding Biology, Faculty of Agrobiology and Food Resources, Slovak University of Agriculture in Nitra, Tr. A. Hlinku 2, 949 76 Nitra, Slovakia
2Department of Animal Husbandry, Faculty of Agrobiology and Food Resources, Slovak University of Agriculture in Nitra, Tr. A. Hlinku 2, 949 76 Nitra, Slovakia

Received August 12, 2019
Accepted September 24, 2019

The aim of this study was to analyse the genome-wide distribution of runs of homozygosity (ROH) segments in the genome of Norik of Muran horse and to identify the regions under strong selection pressure. Overall, 25 animals genotyped by the GGP Equine70k chip were included in the study. After SNP pruning, 54479 SNPs (75.72%) covering 2.25 Gb of the autosomal genome were retained for scan of ROH segments distribution. The ROHs were present in the genome of all animals and covered in average 13.17% (295.29 Mb) of autosomal genome expressed by the SNP loci. The highest number of ROHs was identified on autosome 1 (404), while the lowest proportion of autosome residing in ROH showed ECA31 (38). The footprints of selection, characterized by SNPs with extreme frequency in ROHs across specific genomic regions, were defined by the top 0.01 percentile of signals. Overall, nine genomic regions located on seven autosomes (3, 6, 9, 11, 15, 23) were identified. The strongest signal of selection showed three autosomes ECA3, ECA9 and ECA11. The protein-coding genes located within these regions suggested that the identified footprints of selection are most likely consequences of intensive breeding for traits of interest during the grading-up process of the Norik of Muran horse.

Funding

This study was supported by the Slovak Research and Development Agency (APVV-14-0054 and APVV-17-0060) and VEGA (1/0742/17).

References

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