Furthermore, an IL-2/IL-2RA-dependent proliferation of CD4+ FOXP3+ Tregs could be strongly linked to their efficiency in the immune homoeostasis, as impairment of CD4+ FOXP3+ Treg in T1D occurs primarily because of the inefficient induction and maintenance of Tregs, with deficiencies in IL-2/IL2RA signalling 2,3. This evidence concerns the gene CD4 and type 1 diabetes mellitus.