The T1D susceptibility locus, denoted IDDM8, a region on chromosome 6q27 (Figure 1), spans approximately 200 kb and contains a number of potential candidate genes, including programmed cell death 2 (PDCD2), proteosome subunit beta type 1 (PSMB1), delta-like ligand 1 (DLL-1) and TATA box-binding protein (TBP) amongst others [8]. The gene discussed is DLL1; the disease is type 1 diabetes mellitus.