title: [Genetic variability of type 3 echoviruses].
abstract: The aim of the present work was to assess the genetic and antigenic variability in the VP1 region of type 3 echviruses (E-3), an enterovirus serotype associated to meningitis, neuro-muscular diseases and type 1 diabetes in human. Forty-six VP1 sequences of E-3, among which 9 were isolated in tunisian infants, were included. Phylogenetic analyses and nucleotidic divergence rates were studied in the complete VP1 region and in a 290-nucleotides fragment in the 5' part of the P1. Aminoacid sequences were deduced in the aim to identify genotype-specific antigenetic determinants. E-3 sequences divided into two genogroups, I and II; the genetic variability within the E-3 serotype reached 29.1%. Genogroup I included sequences with a relatively high genetic diversity among each other, some of them grouped in one genotype with at most 15.1% divergence rate. The sequences included in Genogroup II have a maximum of 13.8% divergence corresponding probably to only one genotype. The two genogroups have a concomitant circulation and a wide geographical and temporal distribution. Aminoacid substitutions that may be specific to genogroups, genotypes and special variant were noted. This work provides a first tentative of classification of E-3 into genogroups and genotypes and reports new E-3 sequences from North Africa. It contributes to a better understanding of the molecular epidemiology of human enteroviruses, and of Echoviruses type 3 in particular, a serotype that remains insufficiently studied in the international literature.
authors.affiliation: Laboratoire de référence OMS pour la poliomyélite et la rougeole, Institut Pasteur, Tunis, Tunisie. fwasfi@yahoo.fr
authors.forename: Wasfi
authors.initials: W
authors.lastname: Farès
authors.forename: Dorra
authors.initials: D
authors.lastname: Rezig
authors.forename: Ahlem Ben
authors.initials: AB
authors.lastname: Yahia
authors.forename: Henda
authors.initials: H
authors.lastname: Touzi
authors.forename: Zina
authors.initials: Z
authors.lastname: Meddeb
authors.forename: Henda
authors.initials: H
authors.lastname: Triki
mesh_terms: D000595:Amino Acid Sequence; D002648:Child; D002675:Child, Preschool; D004457:Echovirus Infections / Q000235:genetics / Q000821:virology*; D029822:Enterovirus B, Human / Q000145:classification / Q000235:genetics* / Q000302:isolation & purification; D014644:Genetic Variation; D016679:Genome, Viral / Q000235:genetics; D006801:Humans; D007223:Infant; D008969:Molecular Sequence Data; D010802:Phylogeny; D017423:Sequence Analysis, RNA; D017386:Sequence Homology, Amino Acid; D014416:Tunisia; D015678:Viral Structural Proteins / Q000032:analysis / Q000235:genetics
chemical_list: D015678:Viral Structural Proteins