FYI: HBV Genomes, Genotypes & Strains

liver411

Types of HBV Genomes The following is a list of the major types of HBV genomes found in the human population: 1993: Genetic relatedness of hepatitis B viral strains of diverse geographical origin and natural variations in the primary structure of the surface antigen. 1995: Subtypes, genotypes and molecular epidemiology of the hepatitis B virus as reflected by sequence variability of the S- gene. 1998: Antigenic diversity of hepatitis B virus strains of genotype F in Amerindians and other population groups from Venezuela. 6 Genotypes (A,B,C,D,E,F) [PMID: 8336122] Group A - Orig - N. Europe - Sub-Saharan Africa Group B - Confined to - Eastern Asia (China) Group C - Far East (Japan) Group D - Mediterranean - Near, Mid East, South Asia Group E - W. Sub-Saharan Africa, south to Angola Group F - New World - Brazil, N. + S. America 121 Strains Exist as Quasispecies There are four serotypes which are based on subtypes of the hepatitis B surface antigen (HBsAg). These are defined by two mutually exclusive determinant pairs d/y and w/r with a common determinant 'a'. These subtypes are adw, ayw, adr, and ayr. Four genomic groups of HBV were later referred as genotypes designated with A-D. Sequencing of the S-gene of HBV is the molecular basis for the assessment of the serological variations of HBsAg within the major four subtypes. Two new genotypes of HBV are designated with E and F. The F genotype diverges from other HBV genomes sequenced by 14%. So far, it is the most divergent HBV genome. Worldwide molecular epidemiology of HBV is based on the variability of the S-gene. The E and F strains appear to originate from aboriginal populations of Africa in the New World. [ 此消息由 liver411 在 2001-11-30.08:47:51 编辑过 ]