GSTM1 and GSTT1 Polymorphism in Egyptian Sickle Cell Anemia Patients.

Abstract

Glutathione S-transferase gene deletions are known detoxification agents and cause oxidative damage. In different studies, variations in null allele frequency have been observed. We have investigated the prevalence of the GSTM1 and GSTT1 null genotypes in sickle cell disease (SCD) patients. Thirty-seven sickle cell anemia and forty controls were evaluated to determine the frequency of Glutathione S-transferase (GST) gene deletions. Complete blood counts were performed by an automated cell analyzer. Hemoglobin F, hemoglobin A, hemoglobin A2 and hemoglobin S were measured and diagnosis of patients was achieved by high performance liquid chromatography. The GST null genotype was determined using polymerase chain reaction (PCR) method. The prevalence of GSTM1-null genotype in SCD was 37.8%, compared to 55.0% in the control group (OR=0.9, 95% CI=0.3-2.8, p=0.24). The frequency of individuals carrying GSTT1 null genotype was higher among SCA patients (64.9%) compared to controls (42.5%) (Odds Ratio, OR=2.5, 95% Confidence Interval, CI=1.8-4.2, p=0.015). Present results showed that the frequency of combined polymorphism GSTT1/M1 null genotypes were not statistically significant. GSTT1 and GSTM1 showed no statistical significance between patients and control group in relation to both clinical and laboratory findings. We have observed that GSTT1 null genotypes were high among Egyptian sickle cell anemia patients and both GSTT1 and GSTM1 null genotypes were not related to both clinical and laboratory findings in SCD patients.