In line with observations made in benign nevi, the simple expression of BRAFV600E under the control of the melanocyte-specific MITFA-promoter failed to induce the formation of melanocytic tumors in zebrafish; however, when crossed into a PT53 mutant loss-of-function background, these zebrafish develop nevi, and after several months, melanomas [194]. The gene discussed is MITF; the disease is melanoma.