Association of C677T Polymorphism of Methylenetetrahydrofolate Reductase with Metabolic Syndrome among Eastern Indian Women: A Case-control Study

Abstract

Introduction: Polymorphisms of Methylene Tetrahydrofolate Reductase (MTHFR) gene have been associated with hyperhomocysteinaemia, which in turn may lead to hypertension, insulin resistance and abnormality of lipid metabolism. All these abnormalities are also components of Metabolic Syndrome (MetS). Thus, there is possibility of an association between MetS and MTHFR polymorphism. Literature search revealed paucity of data on this association, particularly from India. Aim: To evaluate the association of C677T polymorphism of MTHFR gene with MetS, among women of eastern Indian population. Materials and Methods: A hospital-based case-control study was conducted in the Department of Biochemistry, Calcutta National Medical College, Kolkata, West Bengal, India, between December 2016 to June 2018. Anthropometric and biochemical profiling of all 417 study subjects were done. Genetic work-up was done by Polymerase Chain Reaction (PCR), using suitable primer, followed by restriction fragment length polymorphism analysis using Hinf 1 enzyme to identify MTHFR C677T polymorphism. Subjects were divided into two groups according to presence or absence of MetS as per International Diabetic Federation worldwide definition and compared with Mann-Whitney U Test. Logistic regression analysis was also performed. Results: Out of enrolled 417 female subjects, 243 were categorised as MetS group. Mean age (in years), of MetS group (48.70±9.03) was found to be significantly higher (p<0.001) than that of control group (42.83±10.90). A total of 45 (25%) females with MetS exhibited the presence of heterozygous CT genotype; that was significantly higher (p=0.026) than the non MetS group 21 (14.9%). The mutant T allele frequency was also significantly higher among the subjects suffering from MetS; 45 (12.5%)compared to 21 (7.4%) in the control group (p=0.036). Multiple logistic regression analysis revealed the odds of developing MetS among subjects with heterozygous CT genotype was 7.721 times (CI: 2.38-25.05) compared to those with wild genotype. Conclusion: C677T polymorphism of MTHFR gene was associated with the occurrence of MetS among woman.

Keywords

• abdominal obesity
• hyperhomocysteinaemia
• hypertension
• insulin resistance