Additionally, a detailed search involving more than 2,000 patients with T1D identified HLA B*39, HLA B*18, and HLA A*24 as being associated with T1D susceptibility, conferring a relative risk comparable to, or greater than, the more classically associated T1D genes, such as PTPN22 (7). Here, PTPN22 is linked to type 1 diabetes mellitus.