These data suggest that clonal overlap of autoreactive CD8 T cells between any two genetically identical NOD mice is extremely low; this validates mathematical predictions of V(D)J recombination diversity (Davis & Bjorkman, 1988; Lieber, 1991), which suggest that 1015 to 1020 TCRs may be randomly generated by an organism, and our laboratory’s prior work on CD4 T-cell clonal diversity in acute viral infection (Khatun et al, 2021). This evidence concerns the gene CD8A and viral infectious disease.