GENETIC DIVERSITY AMONG CLINICAL AND ENVIRONMENTAL ISOLATES OF ASPERGILLUS-FUMIGATUS

To determine if cases of invasive aspergillosis (IA) were caused by st rains of Aspergillus fumigatus with unique characteristics, strains fr om immunosuppressed patients with IA were compared to strains obtained from sputa of patients with cystic fibrosis and to strains from the e nvironment, An extremely high genomic diversity was observed among the 879 strains typed by Southern blotting with a retrotransposon-like el ement from A, fumigatus (C, Neuveglise, J, Sarfati, J, P. Latge, and S , Paris, Nucleic Acids Res, 24:1428-1434, 1996), Analysis of Southern blot hybridization patterns showed the absence of clustering between e nvironmental isolates and clinical isolates from patients with IA or c ystic fibrosis, In addition, strains could not be clustered depending on their geographical location. This study implies that practically an y strain of A, fumigatus is potentially pathogenic and can provoke a c ase of IA when it encounters a favorable environment in an immunosuppr essed host.