Example. Proportion of significant marker-trait associations (Bonferroni adjusted significance threshold) found at different distances from the causal marker. For each QTN, the distance to the next significant association is shown. The bars on the left show the proportion of simulated data sets for which no significant association was found. The simulated models include: 'additive' - 2 QTNs randomly distributed with a variance proportion of 0.05 each; 'epi_rand' - 2 QTNs randomly distributed with a variance proportion of 0.01 each and 0.08 epistatic effect; 'epi_hapl' - 2 QTNs located on a common haploblock with a variance proportion of 0.01 each and 0.08 epistatic effect. Each model was simulated 1000 times.