Although plasma lipid and lipoprotein levels often correlate with atherogenesis21, it remains unexplained why reduced atherosclerosis in Apoe–/–Nhe1+/– mice and Apoe–/– mice receiving bone-marrow from Apoe–/–Fcer1a–/– mice did not affect plasma lipid and lipoprotein levels. Here, FCER1A is linked to atherosclerosis.