Genetic Diversity and Phylogenetic Study of Leishmania Species in Iran by Multilocus Sequence Typing

Background: Leishmaniasis is an important public health parasitic infection, which is endemic in many parts of the world, including Iran. We aimed to investigate genetic diversity and phylogenetic relationship among different Leishmania isolates using multilocus sequence typing (MLST). Methods: Totally, 41 isolates collected either from patients referred to Leishmaniasis Diagnostics and Treatment Center at Tehran University of Medical Sciences, Tehran, Iran or from animals during 2019-2021, were subjected to the study. They included L. major and L. tropica from human, L. infantum from canine, and L. turanica from rodents from different endemic foci of Iran analyzed using MLST including gp63, g6pdh, lack, nagt, and hsp70 genes. Results: A total of 5010 bps was analyzed from each isolate. The three targets, nagt, lack, and g6pdh, generated better topology comparing to the other genes. In the 44 isolates, 22 haplotypes (STs) were identified. Leishmania tropica contained the highest number of haplotypes (n=12) comparing to L. major (n=8), L. infantum (n=1) and L. turanica (n=1). All five genomic loci caused separation of Iranian Leishmania species at the species level, indicating conservation of these genes in the Leishmania parasite. Conclusion: The highest number of haplotypes belonged to L. tropica, indicating that the genetic diversity of this species is higher than that of L. major. It was further confirmed that the MLST is a suitable method to examine genetic variation of Leishmania parasites with respect to evolutionary and epidemiological studies.