Thirteen genetic loci spanning murine chromosome 15 from 15A2 (Mlvi-2) to 15F2-3 (Gdc-1) have been mapped. The genetic distance extends to 55.4 cM. Among 151 animals, only 1 animal with a double cross-over was found. The linear order is unambiguous, with the exception of the distal end on 15F1-3. Our analysis favors the order cen-Ela-1/Hox-3-Wnt-1-Gdc-1-ter. This ordering makes necessary the introduction of three tightly spaced double recombination events around and within the Hox-3 locus. Alternatively, Hox-3 may be most distal, and several double recombinations at the telomere lead to map expansion. Despite the unequal distribution along chromosome 15 of G-versus R-bands, a comparison of distances determined by physical and genetic mapping does not indicate an overt difference in distance between both mapping techniques.