[Recombination of alpha-viruses during mixed infection in cultured cells. Formation of hybrid forms of RNA of Venezuelan equine encephalomyelitis virus and Karelian fever virus in the region of genes for nucleocapsid and envelope proteins].

A recombination of the genomes of VEE and KF viruses, two alphaviruses of different serotypes, takes place in mixed infection of chick embryo fibroblasts and Vero cells with vaccine strain VEE-230 and KF-9298 strain. This recombination resulted in the production of recombinant virions with altered antigenic properties. Polymerase chain reaction (PCR) rapidly and effectively detected the hybrid sites of the genome in recombinant viruses. Short nucleotide sequences (approximately 20 n. p.) of a known primary structure in the RNA genomes, specifically reacting with the complementary PCR primers, were chosen as genetic markers. These data are the first experimental validation of the probable recombinant formation of alphaviruses in nature. They are in good agreement with findings of the recombinant structure of Western equine encephalomyelitis virus genome.