Assessment of genotyping markers in the molecular characterization of a population of clinical isolates of Fusarium in Colombia

INTRODUCTION: Fusarium is a very heterogeneous group of fungi, difficult to classify, with a wide range of living styles, acting as saprophytes, parasites of plants, or pathogens for humans and animals. Prevalence of clinical fusariosis and lack of effective treatments have increased the interest in the precise diagnosis, which implies a molecular characterization of Fusarium populations. OBJECTIVE: We compared different genotyping markers in their assessment of the genetic variability and molecular identification of clinical isolates of Fusarium. MATERIALS AND METHODS: We evaluated the performance of the fingerprinting produced by two random primers: M13, which amplifies a minisatellite sequence, and (GACA)(4), which corresponds to a simple repetitive DNA sequence. Using the Flunter Gaston Discriminatory Index (HGDI), an analysis of molecular variance (AMOVA), and a Mantel test, the resolution of these markers was compared to the reference sequencing-based and PCR genotyping methods. RESULTS: The highest HGDI value was associated with the M13 marker followed by (GACA)(4). AMOVA and the Mantel tests supported a strong correlation between the M13 classification and the reference method given by the partial sequencing of the transcription elongation factor 1-alpha (TEF1-α) and rDNA 28S. CONCLUSION: The strong correlation between the M13 classification and the sequencing- based reference together with its higher resolution demonstrates its adequacy for the characterization of Fusarium populations.