Diagnostic method validation: High resolution melting (HRM) of small amplicons genotyping for the most common variants in the MTHFR gene

ObjectivesAccording to OECD guidelines methods implemented in a diagnostic laboratory should be properly validated prior their implementation. For this purpose we selected genotyping by High Resolution Melting (HRM) of small amplicons using common variants in MTHFR as a model.Design and methodsWe selected previously typed samples on which selected analytical validation-related parameters relevant to DNA diagnostics — specificity, sensitivity, precision, robustness and ability to perform reliable calls were evaluated.ResultsCorrect genotype was assigned in 375/381 (98.4%) for c.677 C > T (rs1801133: C > T; p.A222 V) and in 102/104 (98.1%) for c.1298 A > C (rs1801131: A > C; p.E429A) of all cases. Low analytical failure rate and very high specificity/sensitivity were achieved. Similarly, precision and robustness were consistent.ConclusionsWe have successfully validated HRM of small amplicons using common MTHFR variants as a model. We proved that this technique is highly reliable for routine diagnostics and our diagnostic validation strategy can serve as a model for other applications.