title: KRAS2 as a genetic marker for lung tumor susceptibility in inbred mice.
abstract: An Eco-RI restriction fragment length polymorphism occurring in a DNA fragment containing the first exon of the murine KRAS2 gene was shown to correlate with the inherited susceptibility of inbred strains of mice to urethan (CAS: 51-79-6)-induced pulmonary adenomas. Eco-RI digestion of murine DNA yielded four KRAS2-specific fragments. Polymorphic variation occurred in the smallest molecular-weight fragment with alleles of either 0.70 or 0.55 kb in size. Genotyping of 14 inbred strains of mice revealed a correlation between KRAS2 Eco-RI polymorphic variation and the differential susceptibility among inbred strains to development of pulmonary adenomas. Strains with a high incidence of pulmonary adenomas, either spontaneously occurring or in response to carcinogen induction, had the 0.55-kb KRAS2 allele whereas adenoma-resistant strains had the 0.70-kb allele. Analysis of a series of recombinant inbred strains (AXB, BXA) that developed from reciprocal crosses between a highly susceptible strain (A/J) and a highly resistant strain (C57BL/6J) revealed a statistically significant threefold difference in lung tumor susceptibility on the basis of KRAS2 genotype. Further analysis of individual F2 mice of a C57BL/6 female X A/J male cross also demonstrated a threefold difference in tumor susceptibility on the basis of KRAS2 allelic variation.
mesh_terms: D000236:Adenoma / Q000235:genetics; D000818:Animals; D003433:Crosses, Genetic; D004198:Disease Susceptibility; D005091:Exons; D005260:Female; D005838:Genotype; D008175:Lung Neoplasms / Q000235:genetics*; D008297:Male; D051379:Mice; D008815:Mice, Inbred Strains; D009857:Oncogenes; D012150:Polymorphism, Restriction Fragment Length; D013045:Species Specificity