CAT and cutaneous mastocytosis: While these results suggest that accumulation of O2− or its products (e.g. H2O2) does not play a role in CM pathogenesis, interpretation demands caution, because there are multiple mechanisms for ROS scavenging (e.g. SOD1, SOD2, SOD3, glutathione peroxidase, catalase, heme-oxygenase) in vivo that might have compensated for the lack of SOD1, as recently reported [62].