Phylogenetic analysis of Histoplasma capsulatum based on partial sequence of the D1/D2 region of the 28S rRNA gene.

In order to confirm the phylogenetic relationships of Histoplasma capsulatum, the partial sequences of large subunit (28S) ribosomal gene (D1/D2 region) of 49 isolates were studied. The similarity values of the 49 isolates were more than 99.0% across 617 base pairs, however, the 49 isolates were divided into 9 groups. These 9 groups were independent of 3 varieties, var. capsulatum, var. farciminosum and var. duboisii. These results showed that analysis of the nucleotide sequence of the 28S rRNA gene was very effective for identification of H. capsulatum and that three varieties of H. capsulatum should be reclassified according to the phylogenetic relationship established from analysis of the D1/D2 region sequences.