Use of Random Amplified Polymorphic DNA to Identify Candida Species, Originated from Cancer Patients

Abstract

Introduction: Recently, the incidence of fungal infections dramatically increased with an appearance of many novel species due to different criteria. Therefore, several molecular methods have been established for identification of these agents which cause human and animal disorder based on genomic DNA. Among these methods, RAPD-PCR technique is a powerful discriminative method based on amplifies target genomic DNA sequence by short random primers (arbitrary short primers) with low annealing temperature (36˚C) for discrimination and identification in the species level.
Materials and Methods: All clinical strains were originated oropharyngeal lesions of cancer patients from four Mazandaran University Hospitals in Iran. These strains were previously identified by phenotypic methods such as colony on CHROM-agar Candida medium, germ-tube formation in horse serum and chlamydospore formation. In this study RAPD-PCR technique was used to amplify hyper variable inter-repeat DNA sequences using oligonucleotide primers specific microsatellite (GACA) 4 for identifying, clustering and take into account the genetic correlation of 30 clinical isolates.
Results: The results in this study showed that the RAPD-PCR by using of arbitrary short primer   was able to amplify hyper variable inter repeated DNA sequences with classifying the isolates. RAPD patterns showed genetically inter speciation relationship in the best possible way and PCR-fingerprinting with primer (GACA) 4, was able to discriminate both C. albicans with other Candida species based on size and number of bands.
Conclusion: We concluded that, regarding to the previous studies which have been reported misidentification by conventional mycological method for identifying Candida species, RAPD-DNA method is able to discriminate Candida species by using of a single primer. However, determination of differences and accurate assessment of genetic distances in the RAPD technique was generally limited.