TNF and colorectal cancer: The drug-target mendelian randomization design selects genetic instruments—the single nucleotide polymorphisms (SNPs)—from the vicinity of the TNFR1 gene, instead of from the whole genome, which mimics the effects of the TNF-alpha antibodies (ie, adalimumab) and therefore promotes the clinical translation of the TNF-alpha antibodies into a chemoprevention modality for colorectal cancer.