Association of a murine chromosome 9 locus (Psl1) with susceptibility to mouse skin tumor promotion by 12-O-tetradecanoylphorbol-13-acetate

It has been known for many years that there are dramatic differences in the susceptibility of mouse stocks and strains to two-stage skin carcinogenesis and that these differences are due the animals' responsiveness to tumor-promoting agents. In earlier studies using several inbred mouse strains, we found that susceptibility to skin tumor promotion by phorbol esters such as 12-O-tetradecanoylphorbol-13-acetate (TPA) is a multigenic trait. To extend this work, we conducted a genome scan of (C57BL/6 x DBA/2)F1 x C57BL/6 mice previously scored for sensitivity to skin tumor promotion by TPA. As a result of this scan, we now report an association of increased TPA promotion susceptibility with inheritance of the DBA/2 alleles of markers on the distal portion of mouse chromosome 9. Additional linkage analyses using (C57BL/6 x DBA/2)F2 and B x D recombinant inbred mice confirmed this association and suggested that a TPA promotion susceptibility locus maps near D9Mit51 (LODw = 4.1). We designated this locus promotion susceptibility locus 1 (Ps/1).