No evidence that associations of incident, sporadic colorectal adenoma with its major modifiable risk factors differ by chromosome 8q24 region rs6983267 genotype

A single nucleotide polymorphism (SNP), rs6983267, in the chromosome 8q24 region, has been associated with higher risk for colorectal neoplasms, but its relation to carcinogenic mechanisms is unclear. To investigate whether associations of colorectal adenoma with its major modifiable risk factors differ according to rs6983267 genotype, we performed a pooled analysis of the White participants (n=401 cases, 518 controls) from three colonoscopy-based, case-control studies of incident, sporadic colorectal adenoma conducted between 1991 and 2002. There was a statistically significant direct association of rs6983267 with colorectal adenoma that was consistent with those in previous reports. We found no clear indications that rs6983267 impacts the association of colorectal adenomas with the following risk factors: physical activity, body mass index (BMI), nonsteroidal anti-inflammatory drug (NSAID) use, tobacco or alcohol use, hormone replacement therapy among women, blood 25-OH-vitamin D₃ levels, oxidative balance, or total energy, calcium, red meat, vegetable and fruit, and folate intakes. These findings, together with previously reported null results on 8q24-environment interactions for colorectal cancer, suggest that associations of colorectal adenoma with its major modifiable risk factors may not differ according to chromosome 8q24 region rs6983267 genotype.