In T1D, an inverse correlation was found between CD8+ T cell response and peptide affinity to HLA I (26), and higher frequencies of CD8+ T cells recognizing very low-affinity peptides presented by HLA I than those recognizing the peptides with intermediate affinities (27), indicating that presentation of low-affinity peptides by HLA I might contribute to autoimmunity. This evidence concerns the gene CD8A and type 1 diabetes mellitus.