Strain differentiation of Trichophyton rubrum by randomly amplified polymorphic DNA and analysis of rDNA nontranscribed spacer.
Trichophyton rubrum is the most common pathogen causing dermatophytosis. Molecular strain-typing methods have recently been developed to tackle epidemiological questions and the problem of relapse following treatment. A total of 67 strains of T. rubrum were screened for genetic variation by randomly amplified polymorphic DNA (RAPD) analysis, with two primers, 5'-d[GGTGCGGGAA]-3' and 5'-d[CCCGTCAGCA]-3', as well as by subrepeat element analysis of the nontranscribed spacer of rDNA, using the repetitive subelements TRS-1 and TRS-2. A total of 12 individual patterns were recognized with the first primer and 11 with the second. Phylogenetic analysis of the RAPD products showed a high degree of similarity (>90 %) among the epidemiologically related clinical isolates, while the other strains possessed 60 % similarity. Specific amplification of TRS-1 produced three strain-characteristic banding patterns (PCR types); simple patterns representing one copy of TRS-1 and two copies of TRS-2 accounted for around 85 % of all isolates. It is concluded that molecular analysis has important implications for epidemiological studies, and RAPD analysis is especially suitable for molecular typing in T. rubrum.
Departamento de Análises Clínicas, Faculdade de Ciêlncias Farmacêuticas, UNESP, Rua Expedicionários do Brasil, 1621, Araraquara, SP, CEP 14801-902, Brazil.
Lilian Cristiane
LC
Baeza
Departamento de Análises Clínicas, Faculdade de Ciêlncias Farmacêuticas, UNESP, Rua Expedicionários do Brasil, 1621, Araraquara, SP, CEP 14801-902, Brazil.
Marcelo Teruyuki
MT
Matsumoto
Departamento de Análises Clínicas, Faculdade de Ciêlncias Farmacêuticas, UNESP, Rua Expedicionários do Brasil, 1621, Araraquara, SP, CEP 14801-902, Brazil.
Ana Marisa Fusco
AMF
Almeida
Departamento de Análises Clínicas, Faculdade de Ciêlncias Farmacêuticas, UNESP, Rua Expedicionários do Brasil, 1621, Araraquara, SP, CEP 14801-902, Brazil.
Maria José Soares
MJS
Mendes-Giannini
D021901:DNA, Intergenic / Q000235:genetics*; D004275:DNA, Ribosomal / Q000235:genetics*; D005800:Genes, Fungal / Q000235:genetics*; D014644:Genetic Variation; D006801:Humans; D010802:Phylogeny; D019105:Random Amplified Polymorphic DNA Technique / Q000379:methods*; D015203:Reproducibility of Results; D014005:Tinea / Q000382:microbiology; D014249:Trichophyton / Q000145:classification* / Q000235:genetics*
D021901:DNA, Intergenic; D004275:DNA, Ribosomal