SNP3 and SNP8 are located within the same gene rather than two different genes, so it could be argued that the interaction effect detected in the present study might simply reflect a haplotype effect which implicates a single risk variant effect for CD. But, as noted previously, SNP3 and SNP8 are neither in strong LD (D’= 0.026) nor correlated with each other (r2=0); both SNP3 and SNP8 may have functional implication, suggesting that the interaction is more likely to imply joint effects of two independent and functional variants at the locations of SNP3 and SNP8.
