Article
Comprehensive Analysis of Clinically Significant Hepatitis B Virus Mutations in Relation to Genotype, Subgenotype and Geographic Region
Registro en:
ARAUJO, Natalia M.; TELES, Sheila A.; SPITZ, Natália. Comprehensive Analysis of Clinically Significant Hepatitis B Virus Mutations in Relation to Genotype, Subgenotype and Geographic Region. Frontiers in Microbiology, v. 11, Article 616023, p. 1-22, Dec. 2020.
1664-302X
10.3389/fmicb.2020.616023
Autor
Araujo, Natalia M.
Teles, Sheila A.
Spitz, Natália
Resumen
Hepatitis B virus (HBV) is a highly variable DNA virus due to its unique life cycle,
which involves an error-prone reverse transcriptase. The high substitution rate drives
the evolution of HBV by generating genetic variants upon which selection operates.
HBV mutants with clinical implications have been documented worldwide, indicating
the potential for spreading and developing their own epidemiology. However, the
prevalence of such mutants among the different HBV genotypes and subgenotypes
has not been systematically analyzed. In the current study, we performed large-scale
analysis of 6,479 full-length HBV genome sequences from genotypes A-H, with the
aim of gaining comprehensive insights into the relationships of relevant mutations
associated with immune escape, antiviral resistance and hepatocellular carcinoma
(HCC) development with HBV (sub)genotypes and geographic regions. Immune escape
mutations were detected in 10.7% of the sequences, the most common being I/T126S
(1.8%), G145R (1.2%), M133T (1.2%), and Q129R (1.0%). HBV genotype B showed
the highest rate of escape mutations (14.7%) while genotype H had no mutations
(P < 0.001). HCC-associated mutations were detected in 33.7% of the sequences, with
significantly higher frequency of C1653T, T1753V and A1762T/G1764A in genotype
G than C (P < 0.001). The overall frequencies of lamivudine-, telbivudine-, adefovir-,
and entecavir-resistant mutants were 7.3, 7.2, 0.5, and 0.2%, respectively, while only
0.05% showed reduced susceptibility to tenofovir. In particular, the highest frequency of
lamivudine-resistant mutations was observed in genotype G and the lowest frequency
in genotype E (32.5 and 0.3%; P < 0.001). The prevalence of HBV mutants was also
biased by geographic location, with North America identified as one of the regions
with the highest rates of immune escape, antiviral resistance, and HCC-associated
mutants. The collective findings were discussed in light of natural selection and the
known characteristics of HBV (sub)genotypes. Our data provide relevant information
on the prevalence of clinically relevant HBV mutations, which may contribute to further
improvement of diagnostic procedures, immunization programs, therapeutic protocols,
and disease prognosis.