Abstract: Objectives To identify genotypes of 31 Sporothrix schenckii (S.schenckii) strains by Southern blotting and to explore the relationship between genotypes and geographic distributions and clinical manifestations.Methods Total DNA was extracted by cetyltriethyl ammonium bromide (CTAB).The polymorphisms were detected by hybridization of ApaⅠ-digested S.schenckii genomic DNA with a probe amplified from the small-subunit rDNA and adjacent internal transcribed spacer (ITS) regions.The band patterns manifested by Southern blotting were employed to investigate genotypes of 31 strains of S.schenckii collected from five different areas in China.Results Of 31 strains of S.schenckii,15 individual patterns (DNA Type A-O) were recognized.Type A to C accounted for 51.61% of all strains.Conclusion The Southern blotting provides a highly sensitive and reliable means for DNA typing of S.schenckii.It is also found that there is an obvious correlation between DNA patterns and different geographic distribution and clinical manifestations.

Key words: Sporothrix, DNA,ribosomal, Genotype, Blotting,Southern