title: PCR-based identification of common dermatophyte species using primer sets specific for the DNA topoisomerase II genes.
abstract: BACKGROUND
  We have determined nucleotide sequences of the DNA topoisomerase II genes of the dermatophyte species, and conducted a PCR-based identification system using species-specific primers for the nucleotide sequences.
  
  
  OBJECTIVE
  To identify the major dermatophytes, Trichophyton rubrum, T. mentagrophytes, T. violaceum, M. gypseum, M. canis and E. floccosum, by PCR amplifications at the species level, without determining the nucleotide sequence.
  
  
  METHODS
  For PCR-based identification of the major dermatophyte species, a common primer set (dPsD1) for these species and species-specific primer sets (PsT and PsME) for each species were designed based on the genomic sequences of the DNA topoisomerase II genes of the dermatophytes, and tested for their specificities in PCR amplifications. The method consisted of amplification of the genomic DNA topoisomerase II gene by the common primer set, followed by a second PCR with the primer sets consisting of species-specific primers for each dermatophyte species.
  
  
  RESULTS
  Using dPsD1, a DNA fragment of 3390 bp was amplified from the genomic DNA of all the dermatophyte species. In the subsequent nested PCR using species-specific primer sets (PsT and PsME), both sets amplified unique sizes of PCR products, all of which corresponded to a species of the dermatophytes even in the presence of other fungal DNA.
  
  
  CONCLUSIONS
  We demonstrate that the PCR-based identification targeting the DNA topoisomerase II gene is rapid and simple, and is available as a tool for the identification of the major dermatophyte species.
authors.affiliation: Laboratory of Medical Mycology, Research Institute for Disease Mechanism and Control, Nagoya University Graduate school of Medicine, 65 Tsurumai, Showa-ku, Aichi 466-8550, Nagoya, Japan. tkanbe@med.nagoya-u.ac.jp
authors.forename: Toshio
authors.initials: T
authors.lastname: Kanbe
authors.forename: Yasuhiro
authors.initials: Y
authors.lastname: Suzuki
authors.forename: Atsushi
authors.initials: A
authors.lastname: Kamiya
authors.forename: Takashi
authors.initials: T
authors.lastname: Mochizuki
authors.forename: Machiko
authors.initials: M
authors.lastname: Fujihiro
authors.forename: Akihiko
authors.initials: A
authors.lastname: Kikuchi
mesh_terms: D003883:Arthrodermataceae / Q000235:genetics*; D001483:Base Sequence / Q000235:genetics; D017931:DNA Primers; D004250:DNA Topoisomerases, Type II / Q000235:genetics*; D016533:Mycological Typing Techniques; D016133:Polymerase Chain Reaction; D012680:Sensitivity and Specificity; D013045:Species Specificity
chemical_list: D017931:DNA Primers; D004250:DNA Topoisomerases, Type II