Multilocus genotypes and DNA fingerprints do not predict variation in azole resistance among clinical isolates of Candida albicans

If variation in azole resistance is due to inherent differences in strains of Cannida albicans, as a predominantly clonal organism, then correlation b etween multilocus genotypes and drug resistance would be expected. A sample of 81 clinical isolates from patients infected with human immunodeficiency virus in Toronto, Canada, plus 3 reference isolates were genotyped at 16 l oci, distributed on all linkage groups, by means of oligonucleotide hybridi zations specific for each of the alleles at each locus. These multilocus ge notypes were significantly correlated with DNA fingerprints obtained with t he species-specific probe 27A indicating widespread linkage disequilibrium in the genome. There were 6 multilocus diploid genotypes and 77 DNA fingerp rint types delineated in this sample. Neither the multilocus genotyping nor DNA fingerprinting alone identified all of the 81 types identified by the combination of these two methods. Multilocus genotypes were not predictive of fluconazole resistance, suggesting that resistance is gained or lost too quickly to be predicted by linkage with neutral markers.