Characteristics of first-degree relatives of patients with T1D (FDRs) at stage 0, (FDRs0) and stage 1 (FDRs1) for development of T1D, patients with recent-onset T1D (R-T1D) in insulin-requiring state (IRS), patients in clinical remission of T1D (CR) and healthy controls (CTR) included in CD4+ T cells and TGFβ1 analysis in the peripheral blood. This evidence concerns the gene TGFB1 and type 1 diabetes mellitus.