Ca3 Fingerprinting of Tanzanian and Nigerian Candida Albicans Isolates

Objective: Ca3 fingerprinting of Candida albicans isolates revealed 5 distinct genetic subtypes or clades, with geographical specificity. Clade SA was found to predominate in South Africa while clade E was specific to Europe. The discovery of clade related antifungal resistance strengthened the need to perform a global mapping of C. albicans isolates to provide clinicians and researchers with relevant information. The object of this investigation was to determine the clade distribution of C. albicans isolates from two other countries on the African continent, namely Nigeria and Tanzania. Methods: DNA was extracted from 15 Nigerian isolates obtained from patients attending a clinic in Ile-Ife, while the 35 Tanzanian C. albicans isolates were obtained from patients attending the Muhimbili Medical Centre, Dar-es-Salaam. The extracted DNA was digested with EcoR1, electrophoresed on a 0.8% agarose gel and blotted to a membrane. Hybridisation was performed with the complex Ca3 probed, labelled with 32P. Autoradiograms were analysed with DENDRON software and mixed dendrograms were constructed by including band data from previously analysed isolates. Results: The majority of Nigerian isolates (40%) clustered in clade I while the majority of Tanzanian isolates (25%) clustered in a group, with a SAB value of 0.7, which was devoid of any of the previously identified isolates. None of the Tanzanian or Nigerian isolates co-clustered with any of the previously identified clade SA isolates. Conclusion: Although the fingerprinting data obtained in this study revealed a unique clade distribution, more isolates from a variety of geographical regions in each of the two countries need to be fingerprinted to establish a true regional specificity.