NRAS and uveal melanoma: Constitutive MAPK activation seems to be a common event in both skin and uveal melanomas, although it occurs through different mechanisms: in skin melanoma, through BRAF and NRAS activating mutations (Reifenberger et al., 2004), and in uveal melanoma MAPK activation can occur through GNAQ activating mutations (Populo et al., 2011b; Van Raamsdonk et al., 2009).