Figure 3. Expression of TCR Vα and Vβ genes is associated with amino acid variation in MHC proteins.

(a) Independent associations between Vα or Vβ expression and nucleotide or amino acid variation in the MHC locus (p<0.05 with Bonferroni correction). SNPs are binned according to their genomic position (12Kb bins); points mark centerpoints of the classical MHC genes. For binning by equal numbers of SNPs see Supplementary Fig. 10. (b) and (c) show TCR Vα and TCR Vβ expression variation explained by amino acid variation in classical MHC genes and genetic variability in the MHC locus outside the transcribed regions of classical MHC genes. Values computed using GCTA³³. Dots indicate that the total fraction of variation explained by the MHC gene components was significant at 5% FDR.