Among these mechanisms, we think heterozygote advantage is least likely because, even though in the TB susceptibility null model (that is, without specific MHC alleles) allelic diversity had a significant effect (estimate −1.56, CI −2.63 to −0.50, P < 0.05; Fig. 5a and Supplementary Table 9), when Susu-DRB*13 was included, this effect was not recovered (estimate −0.46, CI −1.70 to 0.78, P = 0.466; Supplementary Table 9). Here, HLA-C is linked to tuberculosis.