Fig. 4

Conformity of the observed effect of combining different genotypes at the MHC and one susceptibility region with an additive and a multiplicative model of combined risk. The non-MHC susceptibility haplotypes are: (d1); (d2); and (d3)—see “Methods” section. Yellow bands, as in Fig. 4, represent the definitional ORs for different non-MHC genotypes actually observed, but which have been re-referenced to a group with the (AP,AP) MHC genotype. The ORs for all MHC genotypes are also those actually observed (Fig. 4). Only haplotype combinations with ≥ 15 or more representations in the WTCCC are shown. Combinations with fewer than 50representations are shaded in pink; combinations with at least 50 representations are shaded in green