Diversidad genética y estructura de la población de Vibrio cholerae en Colombia Genetic diversity and population structure of Vibrio cholerae in Colombia

Pulsed field gel electrophoresis (PFGE) was used to study thirty-four Vibrio cholerae isolates from the Colombian cholera epidemic between 1991 and 1996. Three V cholerae isolates not belonging to the epidemic in Colombia and a V fluvialis isolate were also analysed. The genetic diversity observed for the 38 isolates typified was 0.95, a very similar valué to that obtained by Multilocus Enzyme Electrophoresis (MLEE). No cor reía tion was observed be- tween the variables characterising these isolates (serotype, origin (clinical or environmental), state, electrophoretic type (MLEE) and restriction macro-fragment profile or pulsetype (PFGE)). No evidence of linkage disequilibrium was obtained on evaluating this population with PFGE and MLEE genetic markers. It is suggested that the Vibrio cholerae population in Colombia presents a sexual genetic structure. The lack of evidence for linkage disequilibrium and the absence of correlation between the epidemiological, biochemical and molecular variables available sustains such a hypothesis. It is also sustained by the high valué for genetic diversity obtained which could be reflecting the coexistence of several lines of descent having a high genetic flow amongst them.