Fig. 2.

EtOH-induced hypothermia. a S1 had a greater EtOH-induced hypothermia response than B6, F1, and F2. b Frequency histogram showing approximately normal distribution (dashed line is normal distribution) in the F2 population. c A scan for single-locus main effects found a significant locus on Chr 16 (not shown), which was also detected using additive (black LOD trace) and interacting (red LOD trace) sex covariates, though the effect was merely suggestive with a covariate in the model. Additional loci were found on Chr 7 with an additive sex covariate and on Chr 3 with an interacting sex covariate. The empirical significance threshold P < 0.05 for the scan with an additive sex covariate is indicated by a solid black line. Suggestive thresholds are indicated by dashed lines for the additive sex covariate (black) and interacting sex covariate (red). d Allelic effects for the loci are consistent with a negative dominance deviation of the Chr 16 locus (rs4182243), whereas the Chr 7 locus (rs13479153) is overdominant, and the effects of Chr 3 (rs3710548) are sex dependent such that male heterozygotes have greater hypothermia than homozygotes of either sex and female heterozygotes have less hypothermia. Overall, in the F2 population males had greater EtOH-induced hypothermia scores than females (note that data obtained in the parental lines were from males only, precluding direct comparison with this QTL effect); *P < 0.05. Data are mean ± SEM (colour figure online)