Runs of homozygosity patterns in beef cattle

The study presents an approach to detect selection signals by the scan of runs of homozygosity (ROH) in two beef cattle populations
bred Slovakia. The frequency and distribution of runs of homozygosity in the genome are affected by natural and artificial selection,
recombination rate and structure of the population. After quality control, the final data set included 43,427 single nucleotide
polymorphisms with overall length 2,504 Mb. Across the genome, sixteen regions under strong selection pressure with a total
length of 73.94 Mb were identified. The functional analysis of selection signals revealed several quantitative trait loci for body
structure, fitness and milk production. In the region with a high frequency of ROH reflecting the intense artificial selection genes
related mainly to muscle development (MSNT, ROCK1, LAMTOR5) were observed. Besides, genes related to the control of the
immune system (PTX3, FGL2) and reproduction (ADCYAP1R1) were localized within selection signals. The results confirm the
intention to improve the production and reproduction traits of Charolais and Limousine cattle according to established breeding
objectives for each breed.