Animals from a crossbred beef cattle population were sequenced at low depth (i.e., 0.5×) and different subsets of selected imputed variants were investigated relative to their ability to explain variation in birth weight (BWT) and post-weaning gain (PWG). Variants were classified by both their predicted functional impact and by the consequence of the mutation and partitioned into subsets within these two criteria. When ~ 1 million variants were included in the same genomic relationship matrix, heritability estimates were similar to a 100k chip array. Heritability estimates for BWT ranged from 0.10 to 0.42 dependent on which variant subsets were included. Similarly, estimates for PWG ranged from 0.05 to 0.38. Differences in minor allele frequency were observed among subsets and these differences likely contributed to differences in heritability estimates. Results suggest that linkage disequilibrium between the variants categorized as being less consequential and underlying causal variants is high as indicated by the high percentage of variation explained.

Read the full article in the Journal of Animal Science.