Fig. 3.

A major QTL on chromosome 15 underlies variation in whole brain OMOR concentration after OXY administration (1.25 mg/kg, i.p.). (A) In 133 F2 mice and considering sex and additive covariate, a single genome-wide significant QTL peaked on medial chromosome 15 (LOD = 7.07; P < 0.001) that explained 19% of the sex-combined phenotypic variance. (B) Chromosome 15 QTL plot shows a peak association at 30 cM (68 Mb). (C) At the peak-associated marker, F2 mice sorted by BALB/c genotype precisely recapitulated the result from the parental substrains (J > By) of increased whole brain [OMOR] in females with the homozygous J/J genotype vs. the homozygous By/By genotype.