Although the association of six polymorphisms (i.e., MTHFD1 rs2236225, MTRR rs1801394, SLC19A1 rs1051266, GNMT rs10948059, DNMT3B rs2424913, and FPGS rs1544105) with CHD was detected, the only polymorphism that was consistently associated with CHD (particularly conotruncal CHD) after correction for multiple testing and adjustment for environmental factors was MTHFD1 rs2236225, as seen for both the case–control and family triads study designs. The gene discussed is DNMT3B; the disease is coronary artery disorder.