Genetic Diversity and Chromosomal Variations in the Iranian Leishmania major Strain: Insights into Pathogenicity and...

Area of Science:

• Genomics
• Parasitology
• Medical Entomology

Background:

• Leishmaniasis is a significant global health issue caused by protozoan parasites transmitted by sand flies.
• Cutaneous leishmaniasis (CL), primarily caused by *Leishmania major*, presents diverse clinical forms in Iran.
• Understanding the genetic basis of *L. major* is crucial for addressing disease variability and treatment challenges.

Purpose of the Study:

• To investigate the impact of genetic diversity in *Leishmania major* on clinical manifestations of cutaneous leishmaniasis.
• To analyze chromosomal count variations, single nucleotide polymorphisms (SNPs), and insertions/deletions (Indels) in an Iranian *L. major* strain.

Main Methods:

• Whole genome sequencing of the Iranian *Leishmania major* strain MRHO/IR/75/ER using next-generation sequencing.
• Bioinformatics tools were employed for data alignment, variant calling, and identification of chromosomal variations, SNPs, and Indels.

Main Results:

• Significant karyotypic variations were observed, including monosomy on chromosome 2 and trisomy on chromosomes 5, 13, 28, and 31.
• A total of 144,509 genetic variants (SNPs and Indels) were identified, with 99% located in coding regions.
• Key genes such as *MRPA*, *HSP70.4*, *GP63*, and *CPA* showed substantial alterations, potentially impacting drug resistance and pathogenicity.

Conclusions:

• This study elucidates the genetic diversity of *L. major* and its correlation with disease progression and treatment outcomes.
• The identified genetic variations provide insights into the mechanisms underlying drug resistance and pathogenicity.
• Further functional studies are recommended to validate these findings and their clinical implications.