Interactions of Methylenetetrahydrofolate Reductase Gene Polymorphisms, Folate, and Homocysteine on Blood Pressure in a Chinese Hypertensive Population

Background: High blood pressure is related to cardiovascular diseases. We aimed to explore the interactions of methylenetetrahydrofolate reductase (MTHTR) gene C677T and A1298C mutations and folate/homocysteine (Hcy) status on blood pressure in a Chinese hypertensive population. Methods: The clinical data in the present study derived from a previous trial (NCT00520247). Genotypes in Hcy pathway enzymes were detected by PCR-RFLP methods. Supine blood pressure was measured with a mercury sphygmomanometer. Serum Hcy was measured by high-performance liquid chromatography, and serum folate was measured by chemiluminescent immunoassay. Results: This study showed that hyperhomocysteinemia independently elevated diastolic blood pressure (DBP) (beta (SE): 2.02 (0.85), p = 0.018). Furthermore, individuals with high Hcy and MTHFR1298AC + CC genotypes showed higher DBP than the normal Hcy and 1298AA carriers (beta (SE): 1.81 (0.54), p = 0.001). This correlation was verified by the trend test (p = 0.003). However, polymorphisms of MTHFR C677T, MTR A2756G or MTRR A66G do not affect baseline blood pressure level. Conclusions: The present study demonstrated that the MTHFR A1298C mutation accompanied by hyperhomocysteinemia jointly elevated DBP. Further studies are necessary to confirm the role of these genotypes and Hcy on blood pressure in a larger population.