Methylenetetrahydrofolate reductase genetic polymorphism and the risk of diabetic nephropathy in type 2 diabetic patients

Abstract

BACKGROUND: As indicated by numerous studies, there exists a relationship between the polymorphism of methylenetetrahydrofolate reductase (MTHFR) and susceptibility to diabetic nephropathy (DN) in various populations; nonetheless, the findings remain inconsistent. Therefore, we carried out a meta-analysis to determine the relationship between the MTHFR gene polymorphism and DN susceptibility. MATERIALS AND METHOD: Related studies were identified from PubMed, Cochrane Library, EMBASE, and the China National Knowledge Infrastructure database (time period: from building the library to October 2019). The strength of the association was examined using odds ratios (ORs) with 95% confidence intervals (95% CIs). RESULTS: The findings illustrated that the C677T gene polymorphism was significantly associated with an enhanced susceptibility to DN compared to that with diabetes mellitus in allelic (OR = 1.64, 95% CI = 1.34-2.00, P < .001), dominant (OR = 1.85, 95% CI = 1.40-2.46, P < .001), codominant (heterozygote: OR = 1.67, 95% CI = 1.27-2.21, P < .001; homozygote: OR = 2.55, 95% CI = 1.82-3.57, P < .001), and recessive (OR = 1.89, 95% CI = 1.50-2.38, P < .001) models of the overall population. Moreover, as compared with the healthy controls, a significantly augmented susceptibility to DN was found in all 5 genetic comparison models (allelic: OR = 2.06, 95% CI = 1.58-2.67, P < .001; dominant: OR = 2.52, 95% CI = 1.73-3.69, P < .001; codominant: OR = 3.78, 95% CI = 2.50-5.70, P < .001; recessive: OR = 2.41, 95% CI = 1.96-2.97, P < .001). Furthermore, stratifying data by ethnicity revealed substantially augmented vulnerability to DN in not only Caucasian but also Asian populations. CONCLUSION: The present study suggests that the C677T polymorphism was associated with an augmented susceptibility to DN.