No Association Between GSTT1/M1 Polymorphism in Glutathione S-Transferase (GST) Gene with Cataract in Hypertensive Patients from North India.

ABSTRACT

Age-related cataract has globally emerged as the leading cause visual impairment leading to blindness. Glutathione S-Transferases and their genetic variantsplay an important role in pathogenesis of cataract. This case-control study was carried out to investigate possible association of GSTT1/M1 polymorphism with Cataract risk in North Indians. Our study included 221 individuals, 132 as Cataract cases (70 with and 62 without hypertension) and 89 age and ethnicity matched controls. Genetic polymorphism in GST gene (GSTT1/M1 polymorphism) wasevaluated by multiplexPolymerase Chain Reaction (PCR) technique.The frequencies of the GSTM1-positive and GSTT1-positive in hypertensive cataract cases were 55.71%, 92.86%; while they were 61.29% and 95.16% in cataract cases without hypertension and; 46.07% and 97.75% in healthy controls respectively. The frequencies of GSTM1-null and GSTT1-null in hypertensive cataract cases were 44.29% and 7.14% %; while they were 38.71% and 4.84% in cataract cases without hypertension and; 53.93% and 2.25% in healthy controls respectively. The frequency of GSTT1/M1 positive wild type genotype was 48.57% in hypertensive and 56.45% in normotensive cataract cases while it was 43.82% in control subjects. Our study found no association between GSTT1/M1 polymorphism with cataract but a nearly significant relationship was observed in GSTM1 positive and GSTM1 null genotypes (p=0.065) with cataract in subjects without hypertension. The study needs furtherinvestigation due to limited sample size.