A polymerase chain reaction ‘PCR’ for a quick diagnosis of aspergillosis

A polymerase chain reaction (PCR) was developed from sequencing data generated from a specific target band that is unique for Aspergillus fumigatus DNA digested with EcoR1. The target band was detected through Southern blot hybridization of a non-radioactive probe labelled with DIG-dUTP and DNAs of different aspergilli. The DNA of the target band was purified, concentrated and subjected to sequencing. The size of the sequenced band was approximately 445 bp. One pair of primers was designed and synthesized from the sequencing data of the band. The oligonucleotide primers were specific in amplifying an identical band of A. fumigatus in a population mix containing DNAs of different Aspergillus spp.; Pencillium spp.; yeasts; bacterial and viral organisms that are commonly encountered in clinical specimens of respiratory origin. The reaction proved highly sensitive and as little as 0.0001 microgram of A. fumigatus DNA was detected in the reaction.