AimsTo investigate the pathogenic potential and genotypic diversity of Yersinia enterocolitica biotype 2 strains isolated in Brazil and to compare these strains with other Y.enterocolitica biotypes using ERIC-PCR and PFGE. Methods and ResultsForty strains of Y.enterocolitica biotype 2 (B2) isolated from humans (5), the environment (34) and animal (1), in Brazil over 19years were studied. In addition to these isolates, we also analysed 26 Y.enterocolitica strains belonging to the biotypes 1A, 1B, and 3-5. All of the B2 strains contained the genes inv, ail, ystA, hreP, tccC and myfA. The genes fepD and fes were detected in 39 (975%) strains, virF was found in three (75%) strains, and ystB and fepA were not detected in any strains. The B2 strains showed genotypic similarities of more than 848% by ERIC-PCR and of more than 690% by PFGE. ConclusionsThe pathogenic potential of the B2 strains examined in this study was highlighted by the occurrence of the majority of the virulence markers searched. The results of the ERIC-PCR and PFGE showed that the B2 strains evaluated in this study had a high genotypic similarity, suggesting that these strains differed little over the 19year study period and that the environment was a possible source of contamination of humans and animals in Brazil. Furthermore, the ERIC-PCR technique grouped the strains belonging to Y.enterocolitica biotypes 1A, 1B, 2, 3, 4 and 5 according to their pathogenicity. Significance and Impact of the StudyThis study provided new information about the pathogenic potential and genotypic similarity of Y.enterocolitica B2 isolated from diverse sources in Brazil. Furthermore, ERIC-PCR showed to be a valuable tool for grouping Y.enterocolitica of different biotypes according their pathogenicity.