Erythropoietic protoporphyria (EPP, MIM 177000) is a rare inherited disorder caused by the deficiency of ferrochelatase (FECH; EC4.99.1.1) that catalyzes the chelation of ferrous iron by protoporphyrin IX, in the last step of the heme biosynthetic pathway (Lecha et al., 2009; Balwani, 2019). The gene discussed is FECH; the disease is erythropoietic protoporphyria.