On the other hand, the top downregulated genes formed 4 subgroups and were related to melanogenesis (Wnt5a, Mitf, Pomc, Mc1r, Kit), melanoma (Fgf9, Fgf12, Fgf2), MAPK signaling pathway (Ncam1, Prkcb, Map3k4, Pla2g4a, Mapk14, Mapk11), and aging (Tgfbr1, Il6, Nox4). Here, MAP3K4 is linked to melanoma.