Type 1 diabetes is an autoimmune disorder characterized by progressive destruction of insulin-secreting β cells of the pancreas, in which CD8+ T cells play a critical role. The diversity in the HLA alleles expressed among various racial and ethnic groups leads to great variability in antigen presentation and recognition by CD8+ T cells in the context of MHC class I molecules. To date, studies aimed at identifying disease-relevant antigenic epitopes have focused on using mice transgenic for HLA-A*0201, a common allele, particularly among Caucasians. We present HLA class I typing data from 88 children with type 1 diabetes at the Children's Hospital at Montefiore, where the patient population is ethnically diverse, but largely minority. When categorized into the HLA supertypes A2, A3, B7, and C1, 77% of those studied have alleles belonging to at least one supertype, and of these patients, 65% do not belong to the A2 supertype, which is the supertype represented by the HLA-A*0201 allele. These results support the need for studies using HLA transgenic mice expressing MHC molecules representative of a variety of HLA supertypes, particularly when searching for antigenic epitopes applicable for study among largely urban, minority pediatric populations.