Fig. 3.

Effect of pretraining work and heart weight as covariates on genomewide linkage scans for posttraining work after 4 wk of exercise training in (FVB × B6) F₂ mice. Black line, genomewide linkage scan for posttraining work with no covariates; red line, genomewide linkage scan for posttraining work with pretraining work and heart weight as additive covariates; blue line, genomewide linkage scan for posttraining work with pretraining work and heart weight as interacting covariates. Significant and suggestive LOD thresholds are represented by top (LOD = 3.54) and bottom (LOD = 2.14) horizontal lines, respectively. LOD thresholds were determined by permutation testing using 1,000 permutations with no covariate. Differences in LOD scores (ΔLOD) ≥ 2.0 were found on chromosomes 1, 2, 5, 6, 10, and 17 with interacting covariates.