POPULATION-GENETICS AND STRAIN TYPING OF MICROORGANISMS - HOW TO DETECT DEPARTURES FROM PANMIXIA WITHOUT INDIVIDUALIZING ALLELES AND LOCI

The actual impact of genetic exchange in natural populations of microo rganisms is presently under debate. It is indispensable to precisely e stimate this parameter in order to assess the stability in space and t ime of these microorganisms' genotypes, and hence, their epidemiologic al and medical relevance. Population genetic concepts make it possible to address this question rigorously. Nevertheless, the analyses are m ade difficult by the fact that very often, the genetic markers used do not allow discrimination of individual alleles and loci. This work pr esents some linkage disequilibrium tests usable even under these condi tions, and hence applicable with any class of marker (isoenzymes, RFLP , RAPD, DNA fingerprinting).