FIG. 1.

Schematic representation of the rDNA gene of T. vaginalis. The rDNA gene of eukaryotic organisms is arranged in tandem repeats. The ITS regions are transcribed with the gene and then are removed before the ribosome is assembled. In the rDNA gene of T. vaginalis, ITS1 begins at nucleotide position 1578 and ends at nucleotide position 1658. A point mutation at the 66th position of the ITS1 region (nucleotide position 1644 of the rDNA gene), in which a cytosine is replaced by a thymidine, occurs in less than 15% of the isolates.