Detection of IDH1, IDH2, and NPM1 Mutations in Acute Myeloid Leukemia by High-Resolution Melting Analysis in Comparison with Direct Sequencing and MRD Detection.

Abstract

Background: Acute Myeloid Leukemia (AML) is a heterogeneous type of acute leukemia. Genetic mutations are the most important prognostic factors in AML. Mutations that affect isocitrate dehydrogenase 1 and 2 (IDH1 and 2) genes are associated with poor prognosis, but the nucleophosmin 1 (NPM1) mutation is favorable. In this study, we investigated the efficiency of the High-Resolution Melting (HRM) method for the detection of NPM1, IDH1, and IDH2 mutations, and used it for minimal residual disease detection.

Methods: Formalin-fixed, paraffin-embedded (FFPE) marrow biopsies of 78 patients with AML were analyzed. Mutation detection was performed using the HRM method and the results were compared with those obtained by direct sequencing. The melting temperatures (Tm) were analyzed using the blast cell percentage.

Results: NPM1, IDHs mutations were detected in 28 (35.8%) and 21 (26.9%) samples, respectively. Among all IDH mutations, 13 (16.6%) and eight (10.2%) samples were harboring the IDH-1 and -2 gene mutations, respectively. Based on the HRM results, samples with higher blast cells had a minimal difference in Tm compared to samples with higher blast cells.

Conclusion: Our study is generally distinguished from previous studies based on the desirable characteristics of the HRM method. Regarding mutation detection in low amounts of extracted DNA, the relationship between Tm and the blast percentage is an advantageous characteristic of the HRM method. As shown in a previous study, the use of NPM1 and IDHs for the detection of Minimal Residual Disease (MRD) by HRM is a sensitive method.