TCN2 and type 2 diabetes mellitus: On the other hand, in OW/OB individuals, MTHFD1-rs1076991 (OR = 0.81 (95% CI 0.69–0.95) P = 0.01) and TCN2-rs1801198 (OR = 0.85 (95% CI 0.72–0.99), P = 0.04) showed nominal association with type 2 diabetes.