PPP6C and melanoma: Furthermore, novel driver mutations were identified in Rac family small GFPase 1 (RAC1), AT-rich interactive domain-containing protein 2 (ARID2), protein phosphatase 6 catalytic subunit (PPP6C), and serine/threonine-protein kinase 19 (STK19) through genome-wide studies of a large number of melanomas [11,21].