GENOTYPIC IDENTIFICATION OF CANDIDA SPP. ISOLATED FROM ONYCHOCANDIDIASIS PATIENTS BY PHENOTYPIC METHODS, PCR AND RAPD-PCR

Abstract

Candidal Onychomycosis (COM) is a common nail disease which plays as sources pathogenic reservoir giving a rise to repeated candidiasis infections. This study aimed to evaluate PCR assays and phenotypic tests for identification of yeasts isolated from COM patients. The study included 100 clinically suspected patients of COM attending the main hospital and clinics in Al-Dewania province in the middle of Iraq during September 2011 to April 2012. One hundred yeast isolates were identified morphologically by CHROMagar medium. DNA was extracted from 14 representative’s isolates for accurate identification by PCR and fingerprinted by RAPD-PCR. Phenotypic examination of 100 yeasts isolates on CHROMagar revealed that these isolates were classified into 7 different species belonged to Candida form genus, PCR assay revealed that primer pair ITS1 and ITS4 was successfully amplified ITS1-5.8S-ITS2 rDNA region for 14 isolates of Candida spp. yielding a unique PCR products approximately 510-650bp in length. The results of RAPD-PCR assay showed that both primers (TAGGATCAGA and AGGTCACTGA) were genotyped 14 isolates of Candida into seven main genotypes; three of these genotypes had highly percentage of homologous (80-100%) among related isolates were studied in each Candida isolates, while the others four genotypes had 10-50% homologous. This study concluded that for accurate and prices identification must used PCR and fingerprinted by RAPD-PCR assays, the results of CHROMagar were correlated with gene expression for each Candida isolates, while the results of RAPD PCR assay were correlated with degrees similarity and difference of genotypes for Candida isolates under interest.