MITF and melanoma: Previous transgenic zebrafish melanoma models used oncogenic BRAFV600E (Patton et al., 2005), NRasQ61K (Dovey et al., 2009) and HRasG12V (Michailidou et al., 2009; Anelli et al., 2009) under the melanocyte-specific microphthalmia-associated transcription factor a (mitfa) promoter, coupled to an additional mutation in the tumour suppressor gene p53. In the mitfa-driven HRasG12V transgenic line, melanoma development is rare but secondary mutations in genes involved in the PI3K signalling pathway contribute to its occurrence (Patton et al., 2005; Dovey et al., 2009; Anelli et al., 2009).