FECH and autosomal erythropoietic protoporphyria: Mutations in the FECH gene cause erythropoietic protoporphyria (EPP; OMIM: #177000) (Gouya et al., 2002); the partial deficiency of FECH leads to the accumulation of free-PPIX in bone marrow, erythrocytes, plasma and finally in the liver (Murphy, 2003; Lecha et al., 2009).