Background/aims: To investigate the effects of GSTT1, GSTM1 and GSTP1 gene polymorphism on the stage of hepatitis B infection.
Methodology: This study included 116 healthy controls, 56 normal carriers of hepatitis B virus, 69 chronic hepatitis B patients and 20 cirrhosis patients. The polymorphism of GSTT1, GSTM1 and GSTP1 were determined with real time PCR with LightCycler instrument using hybridization probes in combination with the LightCycler DNA Master Hybridization Probes Kit (Roche Diagnostics). Multivariate binary logistics regression analyses were used for statistical evaluation.
Results: GSTP1 IIe/val genotype was significantly more frequent in the patients with chronic hepatitis B infection and in the patients with cirrhosis (p=0.049 OR: 1.909, 95% CI 0.993-3.668 and p<0.001 OR: 15.238, 95% CI 1.971-117.782 respectively) than in the healthy controls. Similarly, GSTP1 val/val genotype was significantly more frequent in the patients with chronic hepatitis B infection and in the patients with cirrhosis (p=0.006 OR = 6.799, 95% CI 1.712-26.99 and p<0.001, OR: 62.857 95% CI 8.794-449.285 respectively) than in the controls. There was no significant difference in GST IIe/val frequency between the patients with chronic hepatitis B infection and normal carriers of hepatitis B virus, while GST val/val genotype was significantly more frequent in the patients with chronic hepatitis B infection (p=0.030, OR: 6.097, 95% CI 1.192-31.194). Both GST IIe/val and GST val/val genotypes were significantly more frequent in the patients with cirrhosis than in the normal carriers (p=0.001, OR: 12.160 95% CI 1.618-91.360 and p<0.001, OR: 32.154, 95% CI 4.585-225.513 respectively). In addition, there was a significant relation between GSTP1 gene polymorphism and hepatitis stage. In fact, as IIe/val and val/val genotype frequencies significantly increased so did the stage of the disease and tendency towards cirrhosis (p<0.001). The difference in the GSTP1 gene polymorphism did not significantly differ between the healthy controls and the normal carriers of hepatitis B virus. Also, none of the four groups was significantly different concerning the presence of GSTM1 and GSTT1 gene deletions.
Conclusions: The results of this study suggested that GSTP1-val (105) gene polymorphism could be associated with the course of chronic hepatitis B infection.