Applying Runs of Homozygosity to the Detection of Associations between Genotype and Phenotype in Farm Animals

Abstract Text: Runs of homozygosity (ROH) are contiguous stretches of homozygous genotypes which likely reflect transmission from common ancestors and can be used to track the inheritance of haplotypes of interest. In this paper, ROH were extracted from 50 K SNPs and used to detect genomic regions associated with susceptibility to diseases in 468 Holstein-Friesian cows. Diagnosed diseases were categorised as infectious, metabolic, reproductive, locomotive diseases and mastitis. ROH associated with infectious and locomotive diseases and mastitis were found on BTA 12. A region of homozygosity linked with reproductive diseases was detected on BTA 15. ROH associated with infectious, metabolic and reproductive diseases, and mastitis were observed on chromosomes 3, 5, 7, 13 and 18. Previous studies reported QTLs for milk production traits on these regions, thus substantiating the known negative relationship between selection for milk production and health in dairy cattle.

Keywords:

dairy cattle
ROH
association study