ABSTRACT
BACKGROUND: The species of dermatophytes have been identified and classified by morphological and biochemical characterization as well as by mating experiments. But these techniques are either time consuming or lacking specificity. Recently molecular analysis has been introduced to the field of medical mycology. OBJECTIVE: We investigated the phylogeny and taxomomy of the dermatophytes using sequence analysis of the chitin synthase 1 (CHS1) gene. METHODS: 15 species of dermatophytes (6 strains of T.rubrum, 4 strains of T. mentagrophytes subtypes, M. canis, M. gypseum, E. floccosum, T. verrucosum, and T. tonsurans) were cultured on Sabouraud dextrose broth and their DNA were extracted by bead-beating method. Cloning and sequencing of PCR product were done. RESULTS: The size of specific bands among dermatophytes was 615 bp in CHS1 gene. Phylogenetic analysis of sequences revealed that 6 strains of T. rubrum showed genetically identical pattern in intraspecies, but subtypes of T. mentagrophytes were different. The other dermatophytes showed different pattern in interspecies. CONCLUSION: The phylogenetic analysis of CHS1 gene provided useful information for classification and understanding the evolution of dermatophytes species.