Study on ITS1 Gene of Iranian Trichomonas vaginalis by Molecular Methods

Abstract

Background: Trichomoniasis is a worldwide protozoan parasitic disease and metronidazole is a choice drug for its treatment. Because of disease importance in public health and its controversial ideas about the prevalence of drug resistance, this study was carried out.

Methods: Fifty-two suspected vaginal samples were collected from 2006 to 2007 in Gynecology Maryam Hospital, Tehran, Iran. All isolates were examined by microscopic, culture and PCR techniques. The PCR products were analyzed by RFLP and CSGE methods and two suspected samples were sequenced.

Results: Trichomonas vaginalis was identified from all 52 samples. Of 52 isolates, 45 samples were successfully cultured and amplified by PCR except one. Seven were positive only by PCR. Finally, ITS1 fragment was successfully amplified in 51 of 52. CSGE analysis and PCR products digestion by MspI followed by sequencing showed nucleotide mutation at position 209 (C209T) of the ITS1 fragment in two (3.9%) of them.

Conclusion: The results showed mutation in ITS1 fragment of T. vaginalis in two (3.9%) of Iranian isolates which may be related to metronidazole resistance.

Keywords: ITS1 fragment; Mutation; Trichomonas vaginalis.

Fig. 1

The map position of ITS1 and ITS2 in eukaryotic genome

Fig. 2

Electrophoresis of PCR product on agarose

Fig. 3

Agarose gel electrophoresis of RFLP pattern. Lane 1. PCR Product (313bp). Lane 2. 100 bp DNA Ladder marker. Lane 3. MspI digested wild type PCR Product (270 bp). Lane 4. MspI digested mutant type PCR Product (240 bp)