Characterization of Specific RAPD Markers of Virulence in Tri-chomonas vaginalis Isolates

Background: As for human trichomoniasis the host-parasite relationship is very complex, and the broad ranges of clinical symptoms are unlikely be attributable to a single pathogenic mechanism. Specific Random Amplified Polymorphic DNA (RAPD) markers of 490 bp, 720 bp and 460 bp using the primers Tv-5, OPA-6 and OPA-11, respectively, were reported. This was the first description of possible ge­netic virulence markers of the infection by T. vaginalis. The aim of this study was to characterize the specific RAPD markers in order to elucidate their importance on virulence of this illness. Methods: The selected specific RAPD fragments were cloned and sequenced. The obtained sequences were compared by the BLAST algorithm. Results: The nucleotide sequence of the Tv-5490 RAPD marker exhibited signifi­cant similarity to T. vaginalis hypothetical G3 leucine rich repeat (LRR) family pro­tein (e-value: 6e-14) and Giardia lamblia leucine rich repeat protein 1 virus receptor protein (e-value: 6e-14 and 2e-12) ; however, the OPA-6720 and OPA-11460 showed no significant similarity with any coding published sequence. All the evaluated strains showed the presence of the LRR gene. Conclusion: These results demonstrate a possible role of this gene in the viru­lence of T. vaginalis and in the parasite infection with Trichomonas virus as a possible virus receptor. Further analysis of this gene and encoded protein will allow determin­ing the role that they play in the isolates virus susceptible or resistant pheno­types.