GENOTYPING OF Yersinia pestis: VARIABILITY OF THE (CAAA) LOCUS IN NATURAL STRAINS ISOLATED ON THE TERRITORY OF THE FORMER USSR

摘要

The genomic polymorphism of 69 strains of Yersinia pestis from various natural foci of the former USSR with respect to the locus (CAAA)_n was investigated. It was established that it is represented by 10 alleles in the chromosomes, which is evidence of the variability of this locus (diversity index DI = 0.86). Appreciable differences in DI were shown: from 0.24 in the group of vole strains from 7 isolates of the Transcaucasian highland focus to 0.77 in 9 strains from the Central Asian desert focus. It was concluded that allelic polymorphism of the variable locus (CAAA)_n in natural strains of Y. pestis can be used as one of the genetic markers of the strain. The need to improve the oligonucleotide primers used in PCR to increase the accuracy in genotyping is noted.