LYN and neoplasm: Analysis of LYN protein levels in tumours demonstrated that although overall, there was a correlation between cohort genotype and LYN expression, there were a number of cases in which tumours from a Lyn wild-type mouse had very low or undetectable levels of LYN, whereas tumours from mice homozygous for the Lyn flox allele could actually have high levels of LYN expression.