When the true model involves complementary gene interaction (Table 7) analysis of the sum of the raw symptom counts shows striking evidence for all types of G × E at the two loci. Indeed, statistical support for G × E far outweighs that for the additive, dominant and epistatic main effects of the candidate loci. If the effect of one interacting candidate locus is removed from the model, the main effects of the other are grossly overestimated.
