DFR-Typing of Yersinia pestis Strains from the CIS Natural Foci

Different region analysis (DFR-typing) was used for characterization of 275 Y. pestis strains isolated mainly from the CIS natural plague foci. Genomovars (DFR-types) endemic for 27 natural foci were determined. In addition to 32 genomovars described previously 64 novel Y. pestis DFR-types were revealed. 56 genomovars were shown to circulate in CIS and Mongolia. All strains analyzed by DFR-typing, were clustered in accordance with the phylogenetic tree proposed on the basis of combined SNP- and IS 100 -typing data. The discriminatory ability of the method is high enough to distinguish between subspecies, populations and even strains circulating in certain natural plague focus.