Identification of glutathione-S-transferase gene polymorphisms in type 2 diabetes mellitus patients attending Abdullahi Wase Specialist Hospital, Kano State Nigeria

Glutathione-S-transferases (GSTs) are a family of antioxidant enzymes that include several classes with various polymorphisms. This work was aimed at investigating the association between the polymorphisms of the GSTT1 gene and type 2 diabetes mellitus (T2DM). The frequency of GSTT1 genotypes in T2DM patients and non-diabetic controls were studied. A total of 30 diagnosed cases of type 2 diabetes mellitus were selected from the diabetes clinic section of Abdullahi Wase Specialist Hospital, Kano Nigeria. A total of 30 non-diabetic individuals were also selected as control from the outpatient department (OPD) section of the hospital. All the subjects were assessed for fasting blood sugar (FBS), body mass index (BMI), Systolic and Diastolic Blood Pressures (SBP and DBP) and the genotypes of GSTT1 were determined using multiplex polymerase chain reaction (mPCR) techniques. FBS and BMI were significantly high (P<0.05) in diabetics (225.58±83.58mg/dL and 27.53±3.99kg/m² respectively) as compared to the non-diabetic controls (90.85±14.87mg/dL and 21.46±4.36kg/m² respectively). There were no significant differences (P<0.05) for SBP and DBP in the diabetics (125.73±20.72mmHg and 85.83±13.65mmHg respectively) as compared to the non-diabetic controls (117.33±3.04mmHg and 79.90±10.05mmHg respectively). This implies that the body weight of the diabetic patients is increased being a risk factor in diabetes mellitus.  Furthermore, the GSST1 positive polymorphism was present in 95% of the samples analyzed (i.e. diabetics and controls). There was no presence of the deletion polymorphism in the two groups. This implies that there was no association of GSTT1 polymorphisms with T2DM in the studied population; Even though GSTT1 is associated with T2DM in other populations. Other polymorphisms of GST should be studied to ascertain their roles in the pathogenesis of T2DM in this population.