Associations of methylenetetrahydrofolate reductase C677T genotype with blood pressure levels in Chinese population with essential hypertension

Objective: To confirm the association between baseline blood pressure (BP) levels and the methylenetetrahydrofolate reductase (MTHFR) C677T gene polymorphism in patients with essential hypertension. Methods: A total of 347 patients were enrolled from the Dongzhi community in Anhui Province, China. The C677T polymorphism of the MTHFR gene was detected using high-throughput TaqMan allelic discrimination assay. Baseline BP was measured using a standardized mercury-gravity monometer. Results: In the whole sample, the frequency of the MTHFR C677T genotypes CC, CT, and TT were 38.6%, 48.1%, and 13.3%, respectively. In a recessive model (CC+CT versus TT genotypes), baseline diastolic blood pressure (DBP) was significantly higher in patients with the TT genotype compared to those with the CT or CC genotypes (P= 0.013). We also divided all patients into three groups based on the tertiles of the baseline BP distribution. Compared to subjects in the lowest tertile of DBP, the adjusted odds of having the TT genotype among subjects in the highest tertile was 2.6 (95% CI: 1.1 to 6.2). However, no significant associations were observed between baseline systolic blood pressure (SBP) and the MTHFR C677T polymorphism. Conclusions: The MTHFR gene polymorphism could be an important genetic determinant of baseline DBP levels in Chinese essential hypertensive patients.