Genetic variability of hepatitis B virus in Uruguay: D/F, A/F genotype recombinants

Abstract

Hepatitis B virus (HBV) infection is a serious global health problem. Approximately 2 billion people worldwide have been infected, and approximately 350 million individuals currently suffer from HBV-induced chronic liver infection, which causes 600,000 deaths annually from chronic hepatitis, cirrhosis and hepatocellular carcinoma. HBV is classified in eight genotypes (A-H), and two more have been proposed (I-J). In this paper, complete genome sequences of nine Uruguayan HBV are reported. Five samples belong to genotype F1b and one to genotype A2. Three HBV recombinants were detected: A1/F1b, A2/F1b and D3/F1b. The following mutations were detected: a G1896A substitution, a 33-nucleotide deletion from position 2896 to 2928 in the Pre-S1 region involving Pre-S1 residues 3-13, a 33-nt deletion in the Pre-S1 region involving nt 2913-2945 and Pre-S1 residues 9-19. More F genotypes strains than expected were detected in this study, supporting the hypothesis that there are more people of indigenous origin than declared in our population. Also, one third of the samples analyzed were recombinants. This cannot be explained by the low HBV prevalence in Uruguay, but a high HBV infection rate in drug addicts and dialysis patients could act in favor of multiple-genotype HBV infections that could lead to recombination.

High prevalence of HBV infection, detection of subgenotypes F1b, A2, and D4, and differential risk factors among Mexican risk populations with low socioeconomic status

“…The main reasons are the stratification of the population structure comprised of Native Amerindians and genetically-admixed Mestizos (Amerindian, Caucasian, and African lineages) and the concurrent high level of economic inequality. 12 Thereby, the endemic genotype H in Mexico 13 and the F1-F4 subgenotypes of Central and South America [14][15][16][17] correspondingly circulate among natives, rural, or urban, low-income class Mestizo subpopulations. Likewise, genotypes A, D, or B, C that circulate among urban populations of European descendants and Asian immigrants, respectively have been related to liver damage.…”

Characterization of Hepatitis B virus based complete genome analysis improves molecular surveillance and enables identification of a recombinant C/D strain in the Netherlands

“…In addition to the genetic variability, HBV can undergo frequent recombination events adding to the variability of these viruses. More recent recombinants include combinations of genotypes A/B/C, A/C, A/D, A/E, A/D, A/G, C/G, B/D, C/F, C/G, C/J, A/C/G, D/F, F/G, D/F, A/F [ [12] , [13] , [14] ]. Common breakpoints are characterized at the gene boundaries of the preS1/preS2/S and preC/C-gene [ 13 , 15 ].…”