Runs of homocigosity and its association with productive traits in Mexican Holstein cattle

PLoS One. 2022 Sep 19;17(9):e0274743. doi: 10.1371/journal.pone.0274743. eCollection 2022.

Abstract

The objective of this study was to describe the runs of homozygosity (ROH) detected in the Mexican Holstein population and to associate them with milk, fat and protein yields, and conformation final score. After imputation and genomic quality control, 4,227 genotyped animals with 100,806 SNPs markers each were used. ROH with a minimum length of 1 Mb and a minimum of 10 SNPs were included in the analysis. One heterozygous SNP marker and five missing genotypes per ROH were allowed. A total of 425,098 ROH were found in the studied population (71.83 ± 10.73 ROH per animal), with an average length and coverage of 4.80 ± 0.77 Mb, and 276.89 Mb, respectively. The average chromosome length covered by ROH was 10.40 ± 3.70 Mb. ROH between 1 and 2 Mb were the most frequent in the population (51.33%) while those between 14 and 16 Mb were the least frequent (1.20%). Long chromosomes showed a larger number of ROH. Chromosomes 10 and 20, had a greater percentage of their length covered by ROH because they presented a largest number of long ROH (>8 Mb). From the total ROH, 17 were detected in 1,847 animals and distributed among different chromosomes, and were associated with milk, fat and protein yield and percentage, and conformation final score. Of the ROH with effects on production traits, the majority were found with a length between 1 and 4 Mb. These results show evidence of genomic regions preserved by genetic selection and associated with the improvement of the productivity and functionality of dairy cattle.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Animals
  • Cattle / genetics
  • Genome*
  • Genotype
  • Homozygote
  • Inbreeding*
  • Phenotype

Grants and funding

This study was financed by the National Center for Disciplinary Research in Physiology and Animal Improvement of the National Institute for Forestry, Agriculture and Livestock Research in Mexico (CENID F y MA – INIFAP), project with SIGI Number: 15352034772. The funders had no role in the design of the study; in the collection, analyses, or interpretation of data; in the writing of the manuscript, or in the decision to publish the results.