Genetic linkage of nuclear morphology of mouse lung tumors to the Kras-2 locus

Search for quantitative trait loci (QZLs) has been successful in the past d ecade by revealing numerous susceptibility to lung cancer loci in specially designed experimental crosses in mice. Although qualitative aspects of lun g tumorigenesis are also genetically controlled, no loci affecting such tra its have so far been identified. We analyzed a series of lung rumors derive d from various inbred and recombinant congenic strains and F2 crosses for t wo histological characteristics: nuclear cytoplasmic invaginations (NCIs) a nd lymphocytic infiltration (LI) and performed linkage analysis. A signific ant linkage of the Kras-2 locus with presence or absence of NCI was detecte d. The implications of this linkage as well as the relationships between NC I, LI, tumor size and Kras-2 alleles are discussed.