Such autoreactive CD8+ T cells usually undergo negative selection in the thymus, which seems to be altered/impaired in T1DM due, at least partly, to an allelic variant of the nuclear factor kappa-light-chain-enhancer of activated B cells (NF-κB) modulator, NF-κB-inhibitor Delta (Nfkbid), which is an atypical NF-κB inhibitor and an important regulator of B cell immunity across a host of medical conditions [14]. The gene discussed is NFKB1; the disease is type 1 diabetes mellitus.