Regarding studies investigating the association between the MTHFR A1298C polymorphism and CRC risk, there were 43 high-quality studies, 15 moderate-quality studies, and 2 low-quality studies.The genotype distribution in the control groups of all studies, except for 17 [43,44,48,64,69,73,80,83,85,94,111,122,124–126,130,138], was consistent with the HWE test. The gene discussed is MTHFR; the disease is colorectal carcinoma.