We also used GSEA to compare our disseminated ZMEL1-GFP signature to a panel of human melanomas that have been previously classified as ‘invasive' versus ‘proliferative'14, and found that the metastatic zebrafish cells were strongly enriched for the ‘proliferative' signature that is dominated by differentiation-related target genes of MITF such as PMEL, TYR, SLC45A2 and GPR143, (Fig. 2c and Supplementary Data 3, NES=1.317, FDR=0.08). This evidence concerns the gene SLC45A2 and melanoma.