Role of Glutathione S Transferase M1 and T1 Gene Polymorphism in Hepatitis B Related Liver Diseases and Cryptogenic Cirrhosis

Abstract

Progression of hepatitis B virus infection (HBV) might be affected by host genetic factors. The present study was undertaken to study the role of glutathione S-transferases (GST)-M1 and T1 gene polymorphisms in different stages of HBV infection: HBV inactive carrier, chronic hepatitis B and cirrhosis, and cryptogenic cirrhosis. The study population comprised of 170 subjects; 120 cases (HBV inactive carrier, n=30; HBV related chronic hepatitis, n=30; HBV related cirrhosis, n=30; cryptogenic cirrhosis, n=30) and 50 unrelated healthy adults without liver disease as controls. Analysis of GSTM1 and GSTT1 gene polymorphisms was done by multiplex polymerase chain reaction. The GSTM1 null genotype was seen more commonly in hepatitis B cirrhosis (n=21; 70%), chronic hepatitis B (n=19; 63.33%) and cryptogenic cirrhosis (n=17; 56.67%) as compared with inactive carrier (n=9; 30%) and controls (n=13; 26%). The GSTT1 null genotype was seen less frequently in all the groups, the observed frequencies were controls (n=7; 14%), inactive carrier (n=5; 16.67%), chronic hepatitis B (n=8; 26.67%) and hepatitis B cirrhosis (n=7; 23.33%). The difference of GSTM1 null genotype frequencies was statistically significant for hepatitis B cirrhosis vs. controls (P=0.0002), chronic hepatitis B vs. controls (P=0.002) and cryptogenic cirrhosis vs. controls (P=0.01). The GSTT1 null genotype was not found to vary significantly between the groups. The patients with GSTM1 null genotype are at risk of progression of liver disease as the frequency of GSTM1 null genotype was found to be significantly higher in chronic hepatitis B, hepatitis B cirrhosis and cryptogenic cirrhosis as compared with controls.