Fig. 3

Proportion of explained genomic variance by random gene groups for the trait Mastitis 1.2 as a function of number of markers in the gene groups, showing that an increase in group size increases the expected amount of explained genomic variance. The dots corresponds to a random gene group, and the lines are the 50th and 95th percentile of these. The random gene groups are colour coded according to whether the likelihood ratio is larger than 95 % of the likelihood ratios of the same trait. The regression lines are coloured according to whether they describe gene groups containing DGAT1 genes; the grey, dashed line corresponds to the naïve expectation of the infinitesimal model, where all markers contribute with the same effect