Genetic variation in RPOIILS gene encoding RNA polymerase II largest subunit from Leishmania major

Area of Science:

• Parasitology
• Molecular Biology
• Genetics

Background:

• Leishmaniasis is a severe, widespread disease affecting 350 million people globally, with cutaneous leishmaniasis (CL) being a significant form.
• Old World CL is primarily caused by Leishmania species, with outbreaks reported in regions like Iran.
• Recent findings suggest some Leishmania major strains possess internal transcribed spacer 1 (ITS-1) genes homologous to those in the Crithidia genus.

Purpose of the Study:

• To analyze the ITS-1 gene in Leishmania isolates from suspected CL patients.
• To investigate the genetic diversity of the RNA polymerase II largest subunit (RPOIILS) gene in specific isolates.
• To contribute to understanding and managing Leishmaniasis outbreaks in endemic areas.

Main Methods:

• DNA extraction from 100 patient isolates suspected of CL.
• Polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) analysis of the ITS-1 gene.
• Sequencing of ITS-1 and RPOIILS genes for homology and diversity assessment.

Main Results:

• 10% of Leishmania isolates exhibited ITS-1 genes of a different size compared to routine strains.
• Sequencing confirmed these unique ITS-1 genes were similar to those found in Crithidia fasciculata.
• Analysis of the RPOIILS gene revealed significant genetic diversity among the isolates.

Conclusions:

• A subset of Leishmania isolates from CL patients display unique ITS-1 genetic features, potentially linked to Crithidia.
• The observed genetic diversity in RPOIILS highlights the complexity of Leishmania populations.
• Findings offer insights into Leishmania outbreaks and may aid control strategies in endemic regions like Iran.