Abstract
Lung tumor susceptibility (LTS) in the mouse is influenced by multiple loci within the H2 complex. We compared the LTS of two H2 congenic strains with intra H2 recombinations, B10.A(1R) and B10.A(2R), whose genetic difference has been reduced to a region of approximately 50 kilobases within the C4-H2D interval, between Hsp70.3 and G7. After transplacental induction with N-ethyl-N-nitrosourea the load of alveolar lung tumors in strain B10.A(2R) is significantly higher than in strain B10.A(1R) (P < 0.001). For papillary tumors no significant differences were observed. We conclude that the alveolar lung tumor load is influenced by an LTS gene located within the Hsp70.3-G7 interval.