To this end, we crossed the Tg(mitfa:creERt2) melanoma-prone fish with the ubi:zebrabow transgenic line (Pan et al., 2013) to evaluate permanent colour changes in creERt2-expressing cells from default red (RFP) to a stochastic combinatorial expression of three fluorophores upon tamoxifen treatment: cyan (CFP), yellow (YFP) and red (RFP) (Fig. 3A). The gene discussed is CFP; the disease is melanoma.