Enteroviruses show a high degree of sequence variation both between and within serotypes due to the lack of proofreading of the viral RNA-dependent RNA polymerase. In addition, recombination is known to occur not only within but also between different serotypes. We have previously shown that capsid coding sequences of coxsackievirus B4 (CVB4) cluster in several coexisting genotypes (intergenotypic @entity377 difference of 12 % or more) whereas a single lineage of echovirus 30 (EV30) has been prevailing and evolving throughout the last two decades. In the major capsid gene, VP1, clustering of both @entity377 and @entity535 sequences correlates with serotype. We have now determined a 501 @entity377 sequence in the non-structural 3CD region of CVB4 and EV30 field strains. Phylogenetic analysis revealed that sequences of @entity42529 ( @entity4973 -B) were segregated in the 3CD region into three distinct clusters without the VP1-associated serotype/genotype correlation. One of the clusters comprised the E2 strain of CVB4, the EV30 prototype and five other CVB4 field strains whereas the other two clusters, in addition to CVB4 and EV30 strains, also included other @entity4973 -B serotypes. We believe that intertypic recombination is the most likely explanation for the observed incongruence. Similarity analysis based on complete genomes of the CVB4 and EV30 prototypes and the CVB4 E2 strain revealed that a putative recombination spot was mapped within the 2B gene. The incongruence observed in the two genomic domains ( @entity69097 ) suggests a certain degree of independent evolution, which may be explained by interserotypic recombination within an enterovirus species. It is thus difficult to exclude recombination in the history of any given strain.

Evolution of the genome of XXXX : incongruence between phylogenies of the VP1 and 3CD regions indicates frequent recombination within the species.

@entity535 :: ('CHEBI:33704', 'Chemical') :: ['amino acid'] @entity42529 :: ('138949', 'Species') :: ['Human enterovirus B'] @entity377 :: ('CHEBI:36976', 'Chemical') :: ['nucleotide'] @entity69097 :: ('1423;8273', 'Gene') :: ['P1 and P3'] @entity4973 :: ('42005', 'Species') :: ['HEV']
@entity42529 :: (138949,Species) :: ['Human enterovirus B']
