Methylenetetrahydrofolate reductase (MTHFR) C677T Gene Polymorphism (rs1801133) and its association with Essential Hypertension in Sudanese Patients.

Abstract

Background: Hypertension is a multifactorial disease caused by the interaction between genetic and environmental factors. Mutations in the methylenetetrahydrofolate reductase (MTHFR) has been known to be associated with the risk of cardiovascular diseases as well as hypertension. Aim: This study aimed to assess the relationship between the presence of the C677T polymorphism of the MTHFR gene (rs1801133) and the risk of hypertension in Sudanese patients. Method: This is a cross-sectional Hospital based study conducted in Khartoum State–Sudan, during Jan.2018-Oct.2018. The study group consisted of 107 with essential hypertension as patients and 142 age matched normotensive as controls. The genotypes of the methylenetetrahydrofolate reductase (MTHFR) gene polymorphism (rs1801133) were detected by Polymerase chain reaction followed by restriction fragment length polymorphism using HinfI restriction enzyme. The statistical analysis of the results was done using SPSS software package. A p-value < 0.05 was taken as significant. Odds ratio with 95% confidence interval was used to assess the risk of the association. Results: This study showed that high frequency of hypertension was observed among female (63.6%), with no significant gender difference between cases and controls (P-value=0.58). Ninety-three percent of the patients were at 40 years and above with significant difference between cases and controls (P-value =0.0001). The family history of hypertension was significantly increase the disease risk among hypertensive up to three folds (P-value =0.003, OR=3.103, CI=1.454, 6.626). Smoking and lack of exercise; were significantly associated with disease susceptibility (P-value =0.044, P=0.001 respectively). We conducted the genotype analysis for the MTHFR polymorphism (rs1801133) considering the dominant model: the wild type (CC) versus the recessive mutant (CT+TT). The analysis provided an evidence that the mutant CT+TT genotypes were significantly higher in hypertensive group compared to the normotensive controls (P-value = 0.048) with an increased risk of hypertension of up to two folds (OR=1.90, CI=.954, 3795). Diabetes and heart diseases as a complication of hypertension, showed a significant occurrence among hypertensive (P-value =0.002 and P-value=0.0001respectively) compared to their counterpart controls. Conclusion: The results of this study indicates that C677T MTHFR polymorphism is associated with the increased risk of hypertension in our samples. Family history of hypertension and the modifiable risk factors such as smoking and sedentary life were also strongly associated with disease susceptibility.