ABSTRACT
<p><b>OBJECTIVE</b>To investigate the inherent characteristics of Vibrio cholerae (V. cholerae) and other vibrios and their relationship.</p><p><b>METHODS</b>Polymerase chain reaction (PCR), DNA sequence analysis, randomly amplified polymorphic DNA (RAPD) analysis and average linkage cluster analysis were used to study 3 isolates of V. cholerae strains O139, three isolates O1 biotype El Tor, four isolates O1 biotype classical and 3 other vibrios.</p><p><b>RESULTS</b>V. cholerae O139 contained the genomic sequences of ctx A2-B as well as V. cholerae O1. V. cholerae and others vibrios were divided into 4 groups by fingerprint patterns of RAPD, that is (1) V. cholerae O139 and V. cholerae O1 El Tor; (2) V. cholerae O1 classical; (3) V. paraheamolyticus and V. vulnificus and (4) V. flluvialis. V. cholerae O139 DNA fingerprint of RAPD was consistent with the El Tor biotype: average linkage cluster distance was 0, and slightly different from the classical biotype, with a distance of 2.07. It was much more different from vibrio paraheamolyticus and others, with a distance of 6.76 - 8.54.</p><p><b>CONCLUSION</b>V. cholerae and other vibrios are polymorphic in inherent characteristics. The inherent characteristics of V. cholerae O139 are the same as El Tor biotype. O139 may have evolved from the El Tor biotype. The inherent characteristics of vibrio paraheamolyticus are the same as vibrio vulnificus.</p>