Multigenic control of skin tumor susceptibility in SENCARA/Pt mice

Skin tumors induced in mice by initiation-promotion (2 microg DMBA-2 microgTPA) protocols were found to be under multigenic control. Eighty- one N2mice from the cross (BALB/cAnPt x SENCARA/Pt)F1 x SENCARA/Pt that wereeither solidly resistant (no papillomas) or highly susceptible (> or = 7papillomas/mouse) were subjected to a 'genome scan' using 89 microsatellitemarkers to check for associations with susceptible and resistantphenotypes. A locus on Chr 5 (Skts4) was found to control thesusceptibility of SENCARA/Pt mice and the resistance of BALB/cAnPt mice topapilloma formation. In addition, higher than expected linkage scores wereseen for the markers D9Mit271, D11Mit268 and D12Mit56. Further work isrequired to establish whether genes determining papilloma formation arelocated in these regions of the genome. In general, no evidence was seenfor loss of heterozygosity in microsatellite markers on Chrs 5, 9 and 11 in17 microdissected papillomas from (BALB/c x SENCARA)F1 hybrid mice.