Association of Angiotensin-Converting Enzyme and Glutathione S-Transferase Gene Polymorphisms with Body Mass Index among Hypertensive North Indians

Abstract

Objectives: This study aimed to examine the association of angiotensin-converting enzyme (ACE) and glutathione S-transferase (GST) gene polymorphisms with body mass index (BMI) in hypertensive North Indians. Methods: This case-control study was carried out between May 2013 and November 2014 at the Era’s Lucknow Medical College & Hospital, Lucknow, India, and included 378 subjects divided into three groups. One group constituted 253 hypertensive individuals (sustained diastolic blood pressure of >90 mmHg and systolic blood pressure of >140 mmHg) who were subcategorised according to normal (<25 kg/m²) or high (≥25 kg/m²) BMI. The third group consisted of 125 age-, gender- and ethnically-matched normotensive controls with a normal BMI. Gene polymorphisms were evaluated by polymerase chain reaction. The genotypic and allelic frequency distribution among both groups were analysed. Results: A significant difference was found between GST theta 1-null and GST mu 1-positive genotype frequencies among the hypertensive overweight/obese individuals and controls (P = 0.014 and 0.033, respectively). However, no difference was observed in the frequency of ACE polymorphisms. ACE insertion/insertion genotype (P = 0.006), insertion and deletion alleles (P = 0.007 each) and GST theta 1-null and GST theta 1-positive genotypes (P = 0.006 each) were found to differ significantly between hypertensive cases and controls, regardless of BMI. Conclusion: ACE and GST gene polymorphisms were not associated with BMI but were significantly associated with hypertension among the studied group of North Indians.