Genetic diversity and relatedness of Candida albicans isolates from humans and animals in Iran: implications for infection control.

Abstract

Introduction: Candida species are known to be a major cause of fungal infections in both humans and animals worldwide. Understanding the local epidemiology and genetic diversity of Candida albicans is essential for effective control and prevention of infections on a global scale. In this study, we aimed to evaluate the genetic relatedness between human and animal isolates of Candida albicans in Iran.

Methods: Thirty-six isolates of C. albicans were obtained from both human and animal sources and were subjected to random amplified polymorphic DNA-polymerase chain reaction (RAPD-PCR) using three primers (OPE-04, OPE-18, and OPA-18). Identification, antifungal susceptibility testing, and virulence profiling were carried out using standardized methods.

Results: Our analysis revealed a significant genetic separation between human and animal isolates of C. albicans, with distinct genotypes identified in each group. Some degree of genotypic relatedness was observed, but with varying levels of separation. The highest genetic similarity (84%) was observed between C. albicans isolates from cow feces and human high vaginal swabs, indicating genetic relatedness but not clonal identity. No clonal relationship was detected among the isolates.

Conclusion: Although this study represents a preliminary investigation, our findings suggest a high discriminatory power of the three primers used in RAPD-PCR for typing Candida isolates. While RAPD-PCR effectively identified genetic diversity, its reproducibility and resolution remain limited, necessitating further validation using more precise molecular methods. The lack of clonal relationship and the observed genetic diversity highlight the potential for transfer of virulent and resistant strains between humans and animals. Further studies with larger sample sizes are needed to validate these findings and to assess the implications of close contact between humans and animals in the transmission of Candida infections.