GLUL and type 1 diabetes mellitus: Cobalamin deficiency as a result of pernicious anemia occurs frequently in patients with T1DM—patients with T1DM actively exhibit autoantibodies to intrinsic factor type 1 and 2 and parietal cell antibodies, in particular those with glutamate decarboxylase-65 antibodies and HLA-DQA1*0501-B1*0301 haplotype [172].