A 12-month randomized controlled trial conducted in youth with new-onset T1D demonstrated that vitamin D2 (a.k.a. ergocalciferol; dose: 50,000 IU/week for 2 months, and then once every 2 weeks for 10 months) significantly reduced serum tumor necrosis factor (TNF)-alpha concentration and the rates of increase in HbA1c and insulin dose-adjusted HbA1c (IDAA1c) [84]. The gene discussed is INS; the disease is type 1 diabetes mellitus.