Restriction fragment length polymorphism analysis of azole-resistant and azole-susceptible Candida albicans strains

Restriction fragment length polymorphism analysis was performed with the endonucleases EcoRI, Bglll, and HinfI on a collection of Candida albicans strains comprising eight strains randomly selected from clinical microbiology laboratory specimens, three reported azole-resistant strains from treatment failures, and several subcultures of the azole-resistant strain NCPF 3310 (also known as the Darlington strain) received from different laboratories. The results demonstrated a diversity of the restriction fragment length polymorphism patterns that were obtained and revealed that two of the proposed Darlington subcultures had patterns distinct from each other and from those of the other Darlington isolates; both were also found to have lost their azole resistance. Previous epidemiological study of Candida albicans has relied upon various phenotypic techniques such as morpho-typing (10), resistotyping (13), and biotyping (9). More recently, genetic analyses by restriction fragment length polymorphisms (RFLPs) have been applied (8), and several DNA probes have been developed for Southern blotting to endonuclease-digested DNA (7, 14)