There was no statistically significant difference between the genotypes in mitotic counts (ApcMin/+, K-ras+/+: 25.3; ApcMin/+, K-rastmΔ4A/tmΔ4A: 26.8; P = 0.468) or apoptotic counts (both genotypes: 2.1; P = 1.0) in the tumours. This evidence concerns the gene KRAS and neoplasm.