Biography
Biography: Osama Hasan Othman
Abstract
Hepatitis itself is not a genetic disease. Hepatitis B virus got genetic diversity. HBV is DNA virus which replicates by RNA intermediate as its DNA polymerase has reverse-transcriptase RT. The mutation rate for HBV is high. HVB classified on base of genomic sequencing, antigenic subtypes of glycoprotein surface antigen HBsAg. Genotype-subtype has geographical distribution related to population movement and significant events. Mutation and mutant selection occurred among all HBV variants. They have relevant medical and public health implications. Pre-core (pre-C) defective variant has less susceptibility to Interferon with high failure rate to other antiviral drugs related to selection of resistant variants mutation in genome encoding viral RT activity. As RT overlaps HBsAg molecule code, selection of drug resistant variants indirectly leads to selection of HBsAg variants commonly encountered in chronic HBV carriers. The significance of this emerges under the pressure of neutralizing antibody response leading to resistance to both vaccination and immunotherapy noted often among liver transplant recipients and babies born to HBV-carrier. HBsAg variants also associated with false negative results in diagnosis of new infections, detection of chronic carriers, screening for blood donation and manufacture of therapeutic blood products.
Speaker Presentations
Speaker PPTs Click Here