Analysis of the Molecular Evolution of Hepatitis B Virus Genotypes in Symptomatic Acute Infections in Argentina

RODRIGO B; MOJSIEJCZUK LN; TORRES C; SEVIC I; GONZÁLEZ LÓPEZ LEDESMA MM; PEREZ PS; BOUZAS MB; GALDAME O; MARCIANO S; FAINBOIM H; FLICHMAN D; CAMPOS R

PLOS ONE

PUBLIC LIBRARY SCIENCE

Lugar: San Francisco; Año: 2016

1932-6203

Hepatitis B virus (HBV) is a globally distributed human pathogen that leads to both self-limitedand chronic infections. At least eight genotypes (A-H) with distinct geographical allocationsand phylodynamic behaviors have been described. They differ substantially in manyvirological and probably some clinical parameters. The aim of this study was to analyze fulllengthHBV genome sequences from individuals with symptomatic acute HBV infectionsusing phylogenetic and coalescent methods. The phylogenetic analysis resulted in the followingsubgenotype distribution: F1b (52.7%), A2 (18.2%), F4 (18.2%) and A1, B2, D3 andF2a 1.8% each. These results contrast with those previously reported from chronic infections,where subgenotypes F1b, F4, A2 and genotype D were evenly distributed. This differentialdistribution might be related to recent internal migrations and/or intrinsic biologicalfeatures of each viral genotype that could impact on the probability of transmission. Thecoalescence analysis showed that after a diversification process started in the 80s, the currentsequences of subgenotype F1b were grouped in at least four highly supported lineages,whereas subgenotype F4 revealed a more limited diversification pattern with mostlineages without offspring in the present. In addition, the genetic characterization of thestudied sequences showed that only two of them presented mutations of clinical relevanceat S codifyng region and none at the polymerase catalytic domains. Finally, since the acuteinfections could be an expression of the genotypes currently being transmitted to newhosts, the predominance of subgenotype F1b might have epidemiological, as well as, clinicalrelevance due to its potential adverse disease outcome among the chronic cases.