Unique surface gene variants of hepatitis B virus isolated from patients in the Philippines.

Point mutations and multiple variants across the "a" determinant can destroy the antigenicity and immunogenicity of hepatitis B virus (HBV) leading to false negative assay and vaccine escape. In this study, the presence of surface gene variants of HBV was investigated among patients clinically diagnosed with chronic hepatitis B and positive for HBV DNA from 2002 to 2009. Sequence analysis of the surface gene of HBV showed that 23 (43%) of the 53 isolates had variations.

Association of glutathione S-transferase T1 and M1 genotypes with chronic liver diseases among Filipinos.

The glutathione S-transferase (GST) supergene family is made up of four gene families responsible for the biotransformation of drugs and other xenobiotics. Genetic variations in this supergene family influence individual detoxification levels and may contribute to the development of cancer. A hospital-based case-control study was conducted to evaluate the association between GST polymorphism among Filipino patients positive for hepatitis B virus (HBV DNA) and clinically diagnosed as either with chronic active hepatitis, liver cirrhosis, and hepatocellular carcinoma as well as normal individuals negative for HBV infection.