Viruses, Vol. 12, Pages 1061: Genetic Diversity Analysis of Coxsackievirus A8 Circulating in China and Worldwide Reveals a Highly Divergent Genotype

In this study, complete genome sequences from 11 CV-A8 strains isolated from HFMD patients in extensive regions from China between 2013 and 2018 were determined, and all sequences from GenBank were retrieved. A phylogenetic analysis based on a total of 34 complete VP1 sequences of CV-A8 revealed five genotypes: A, B, C, D and E. The newly emerging genotype E presented a highly phylogenetic divergence compared with the other genotypes and was composed of the majority of the strains sequenced in this study. Markov chain Monte Carlo (MCMC) analysis revealed that genotype E has been evolving for nearly a century and somehow arose in approximately 2010. The Bayesian skyline plot showed that the population size of CV-A8 has experienced three dynamic fluctuations since 2001. Amino acid residues of VP1100N, 103Y, 240T and 241V, which were embedded in the potential capsid loops of genotype E, might enhance genotype E adaption to the human hosts. The CV-A8 whole genomes displayed significant intra-genotypic genetic diversity in the non-capsid region, and a total of six recombinant lineages were detected. The Chinese viruses from genotype E might have emerged recently from recombining with European CV-A6 strains. CV-A8 is a less important HFMD pathogen, and the capsid gene diversity and non-capsid recombination variety observed in CV-A8 strains indicated that the constant generation of deleterious genomes and a constant selection pressure against these deleterious mutations is still ong...
Source: Viruses - Category: Virology Authors: Tags: Article Source Type: research