Abstract

In this study, we investigated the impact of adaptive positive selection on each protein in Open Reading Frame (ORF) (except for 3D^pro) of serotype O Foot-and-Mouth disease (FMDV). The majority of residues under positive selection were located in antigenic sites or close to heparin interacting regions. There were five identical positions between positive selection sites and substitution sites occurred in three FMDV O/Mya-98 strains (O/JX/CHA/2010, O/VN/LC169/2009 and O/HKN/20/2010) prevalent in Southeast Asia during 2009-2010. In addition, no significant recombination signal was detected in ORF of the Eurasian (Asia1, A, C, and O) serotypes including the three strains above, the result indicated no recombination events occurred in the three strains. We inferred selection and amino acid mutation contributed greatly to the prevalence of the three strains during 2009-2010. 

Key words: Foot-and-Mouth disease (FMDV), Mya-98, positive selection, mutation, recombination