Zebrafish heterozygous at the key BRAF and p53 melanoma driver loci had thicker and darker melanocyte stripes, with minor melanocyte expansion into the interstripe as compared with WT AB* fish (Figure 1, B and C and Supplementary Figure S1), consistent with the melanocyte pattern seen with homozygous BRAFV600E shown previously (Patton et al. 2005). The gene discussed is TP53; the disease is melanoma.