Grouped V gene analysis. (A) Heat maps of TCR V gene usage changes after thymic selection. Red represents the V genes that were overpresented after thymic selection, yellow were the ones unchanged, and gray to blue were ones that were underrepresented. Values were calculated as log₂ of the ratio of Frequency V_in-frame/Frequency V_out-of-frame. (B) V genes were grouped into overrepresented, unchanged, or underrepresented, and their CDR3 length distributions are shown in bars (mean ± SD). Gaussian distributions were assumed and are shown in lines for all groups. Data are from ABabDII mice (n = 5), ABabDR4 mice (n = 5), and humans (n = 3).