RNA homology and the reclassification of Pneumocystis.

The identification of sequence similarities in ribosome RNA subunits from Pneumocystis and certain fungi has led to the suggestion that this presumed protozoan be reclassified as a fungus. However, the absence of predictable characteristics from the fungi as a group to Pneumocystis as a genus indicates that we should wait until additional rRNA coding sequences of more organisms have been compared.