[Molecular epidemiology of Sporothrix schenckii]

Restriction fragment length polymorphism (RFLP) in mitochondrial DNA (mtDNA) of clinical and environmental isolates of Sporothrix schenckii was investigated. Among mtDNA RFLP patterns with Hae III, of 14 environmental isolates morphologically identified as S. schenckii, only 2 isolates were confirmed as S. schenckii, while of more than 500 clinical isolates, all were confirmed to have this condition. Therefore, RFLP analysis of mtDNA is essential for the identification of environmental, but not clinical, isolates of S. schenckii. Isolates of Sporothrix schenckii were classified into 23 mtDNA types (Types l-23) based on mtDNA RFLP patterns with HaeIII and clustered into two major groups by phylogeny, Group A (Types 1-3, 11, 14-19, 22 and 23) and Group B (Types 4-10, 12, 13, 20 and 21). Group A isolates are predominant in South Africa, North America, Central America and South America, while Group B isolates are predominant in Australia and Japan. In Japan, the relative distribution of the mtDNA types varied with geographic region: Types 4, 6 are comparatively abundant in West Japan (Kansai and Kyushu districts), Type 5 is comparatively abundant in East Japan (Tokai, Kanto and Tohoku districts) and Type 2 is abundant in the Hokuriku district. Type 1 is found only in the Hokuriku district.