Semi-quantitative PCR analysis of the Lynfl and Lynwt alleles demonstrated that the abundance of the Lynwt allele in primary cultures of BlgCre Brca1fl/fl p53+/− Lynfl/wt tumours was approximately half that in cultures of BlgCre Brca1fl/fl p53+/− Lynwt/wt tumours, as expected (Fig. 3D,E). Here, TP53 is linked to neoplasm.