When the data were stratified by PPARGC1A genotype, the association of a pro-inflammatory diet with colorectal cancer risk was significantly more pronounced among those carrying rs3774921 homozygous variant allele (OR [95% CI] = 5.15 [2.35–11.29] for high vs. low DII); the association for the wild-type allele was much weaker (OR [95% CI] = 1.63 [1.31–2.02] for high vs. low DII) (P for interaction = 0.009). The gene discussed is PPARGC1A; the disease is colorectal cancer.