An Assessment by Competition Hybridization of the Sequence Homology between the RNAs of the Seven Serotypes of FMDV

A comparison has been made of the RNAs of the seven serotypes of foot-and-mouth disease virus (FMDV) by competition hybridization. Homology among the three European serotypes A, O, C and the Asia 1 serotype was 60 to 70%. Similar homologies were found among the three Southern African Territories serotypes (SAT 1, SAT 2, SAT 3), but homology between the two groups was much lower (25 to 40%). Homology between the RNAs of subtypes within serotypes A and O was greater than 70%. Double competition experiments with the European serotypes indicate sharing of nucleotide sequences.