On the other hand activated H-Ras has been shown to promote ROS production in a variety of human cancer cell types including transformed embryonic lung cells, fibroblasts, neuroblastoma cells as well as in hematopoietic progenitor cells where the promotion of superoxide and H2O2 production through activation of NADPH oxidase was shown [43]–[46]. The gene discussed is FMO5; the disease is cancer.