Mice with homozygous BALB/c alleles at these two loci had significantly shorter latency than those that were heterozygous (one allele from BALB/c and one from SPRET/EiJ) (Figure 2B and 2C), suggesting that some SPRET/EiJ genes delay tumor development in exogenously-grafted BALB/c Trp53 null epithelial fragments. The gene discussed is TP53; the disease is neoplasm.