“…Since mutations are influenced by both environment and genetics, the distribution of snp and mutations is region-specific and race-specific. [ 46 , 47 ] SMAD7, as an inhibitor of the TGF- β signaling pathway, blocks TGF- β signaling through a negative feedback loop, and due to this inhibitory function, SMAD7 can antagonize a variety of TGF-beta-regulated cellular metabolic processes, for instance, cell proliferation, cell differentiation, apoptosis, adhesion, and migration, then impacting CRC progression. [ 3 , 5 , 48 ] By including the maximum number of case–control studies to date, this analysis also consistently concluded that both the T allele of rs12953717 and the C allele of rs4464148 increased the risk of CRC whereas high expression of the C allele of rs4939827 reduced the risk of CRC.…”