Restriction endonuclease analysis of Aspergillus fumigatus DNA.

AIMS To develop a genome based DNA fingerprinting system for Aspergillus fumigatus mould. METHODS DNA was extracted from 21 isolates obtained from eight patients with an aspergilloma. This was with a freeze-dried mycelial extract fragmented in liquid nitrogen. DNA was subsequently purified by phenol-chloroform extraction followed by ultracentrifugation on a caesium chloride gradient. The DNA was restricted by EcoRI and Xba I. RESULTS All isolates were identical when cut by EcoRI; Xba I delineated six DNA types. CONCLUSIONS DNA fingerprinting can be used to type isolates of A fumigatus. Strains from within an aspergilloma which were morphologically distinct could either have the identical DNA fingerprint or produce a unique type.