Molecular analysis of the hepatitis B virus presurface and surface gene in patients from eastern China with occult hepatitis B

This study was designed to detect and analyze mutations that occur within the presurface and surface (pre‐S/S) gene of HBV in patients with occult hepatitis B, and determine their relationship to that disorder. Among 254 HBsAg negative samples of blood collected in eastern China, 183 were positive for anti‐HBc alone, 61 were positive for anti‐HBe alone, and 10 samples were positive for HBeAg. Within this group, 15 samples were found to be HBV DNA positive by real‐time PCR and were designated Group I. A control group of 28 HBsAg positive samples were chosen at random from patients with chronic hepatitis B and designated Group II. The HBV pre‐S/S gene was amplified by PCR and subjected to sequencing analysis. Occult hepatitis B was found in 1.6% of the patients with anti‐HBc alone and in 3.3% of those with anti‐HBe alone. Occult hepatitis B also was found in all HBsAg negative but HBeAg positive samples. Sequencing analysis showed a significant correlation between point mutations within the “a” determinant and occult hepatitis B (P