RESUMEN
This study was designed to determine the correlation of hepatitis B virus surface Ag [HBsAg] variations with the clinical/serological pictures among chronic HBsAg positive patients. The surface gene [S-gene] was amplified and directly sequenced in twenty-five patients. Eight samples [group I] contained at least one mutation at the amino acid level. Five showed alanine aminotransferase [ALT] levels above the normal range of which only one sample was anti-HBe positive. Group II [17 samples] did not contain any mutation, 4 were anti-HBe positive and 9 had increased ALT levels. In both groups, from a total of 18 mutations, 5 [27.5%] and 13 [72.5%] occurred in anti-HBe and HBeAg positive groups respectively. The small number of amino acid mutations might belong to either the initial phase of chronicity in our patients; or that even in anti-HBe positive phase in Iranian genotype D-infected patients, a somehow tolerant pattern due to the host genetic factors may be responsible