Extremely Non-uniform: Patterns of Runs of Homozygosity in Bovine Populations
Runs of homozygosity (ROH) are regions of the genome that are contiguously homozygous because the parents of an individual have transmitted identical haplotypes. . The distribution of ROH along the genome has been shown to be extremely non-uniform in human populations. We have analyzed patterns of runs of homozygosity from the Illumina BovineHD BeadChip for the taurine cattle breeds Angus, Brown Swiss and Fleckvieh as well as for the indicine breeds Brahman, Gir und Nelore. ROH of lengths >1 Mb were accepted.
ROH islands, i.e. regions with highest incidences (>.40) were partly overlapping and partly distinct between subspecies and breeds within subspecies. ROH islands were surprisingly gene rich compared to equally sized regions in distant regions of the same chromosomes. The genesis and function of ROH islands is still unclear and worth pursuing.
Runs of Homozygosity