CYB561 and neoplasm: Finally, the two last members of the cytochrome family we found, namely CG10337 (gene class 6) and CG13077 (gene class 2) with no known function [11], belonged to the Cytochrome b561 subfamily, which consists of transmembrane proteins involved in several processes, such as stress defense, iron metabolism, tumor suppression, and various neurological processes [49].