Direct mutations in Foxp3 gene culminate in severe immune deregulation and polyglandular forms of autoimmunity called the human IPEX syndrome or in the mouse, the Scurfy mouse.15, 16 In lupus, there is an activation defect yielding an overabundance of rTregs and an underabundance of aTregs.5 In type 1 diabetes (T1D), early studies reported reductions in Treg absolute numbers, but more recent, larger and methodologically driven studies have not found such alterations. Here, FOXP3 is linked to type 1 diabetes mellitus.