Atypical URA5 gene restriction fragment length polymorphism banding profile in Cryptococcus neoformans strains

URA5-RFLP is one of the most widely used genotyping methods relating to Cryptococcus neoformans and C. gattii consensus genotype nomenclature. In order to identify a molecular type, this method uses a visual comparison of digested PCR products of tested and reference strains, therefore any anomaly in RFLP patterns of studied isolates makes recognition difficult or impossible. This report describes a strain of VNIV type showing an atypical URA5-RFLP pattern as well as a group of AD hybrids displaying the same anomaly. The atypical RFLP pattern is the result of a point mutation and emergence of a new restriction site. Emergence of the allele presenting a new banding pattern may lead to misidentification using the URA5-RFLP technique; the results of this study as well as the literature data may suggest the spread of the allele in the environment.