CHROMOSOMAL LOCALIZATION OF OPIOID PEPTIDE AND RECEPTOR GENES IN THE MOUSE

Opiate receptors are the primary targets for the drugs of abuse morphi ne and heroin. In this study, we completed the localization on mouse c hromosomes of the genes encoding mu (Oprm) and kappa (Oprk) receptors, as well as the genes for the opioid propeptides proenkephalin (Penk) and prodynorphin (Pdyn). The genetic mapping was performed using a pan el of DNA samples from an interspecific cross [C3H/HeJ-gld and (CSH/He J-gld x Mus spretus)F-1] that has been characterized for more than 800 markers throughout the genome. The genes are localized on mouse Chr 1 (Oprk, 10 cM from the centromere), Chr 2 (Pdyn, 75 cM from the centro mere), Chr 4 (Penk, 1 cM from the centromere) and Chr 10 (Oprm, 10 cM from the centromere). Interestingly, the gene for the mu receptor is l ocated in the same region as a Quantitative Trait Locus for high morph ine consumption, thus raising the possibility of its direct role in dr ug abuse mechanisms.