Human dermal melanoma cells expressing the wild-type G6PD gene (A375-WT), G6PD-deficient A375 cells (A375-G6PD∆), and A375-G6PD∆ cells with overexpression of normal G6PD cDNA (A375-G6PD∆-G6PD-WT) and mutant G6PD cDNA (A375-G6PD∆-G6PD-G487A) were administered to mice in order to compare the time of initial tumor formation, tumor size, and pathological changes. The gene discussed is G6PD; the disease is melanoma.