Rapid detection of IDH2 (R140Q and R172K) mutations in acute myeloid leukemia

Abstract

NADP-dependent enzyme isocitrate dehydrogenase (IDH) mutations, IDH1 and IDH2, have been described in acute myeloid leukemia (AML) using next generation sequencing approaches. IDH2 mutations are heterozygous; they alter a single arginine residue at position 140 or 172 and have distinct prognostic significance. The current detection methods of IDH2 mutations are laborious and time consuming as they require DNA sequencing. Herein, we report a new allele-specific oligonucleotide-polymerase chain reaction (ASO-PCR) method to detect the IDH2 mutations. Analysis of leukemic DNA samples from 120 AML patients enabled to identify IDH2 mutations in 22 cases which were confirmed by direct DNA sequencing. Of these, 17 harbored IDH2 (R140Q) and 5 IDH2 (R172K) mutations. Serial dilution experiments showed that the assay enable to detect mutations in 10⁻³ dilutions. Our ASO-PCR method appears useful for routine diagnostic screening of these prognostically relevant alterations in AML and may be conveniently included in the diagnostic workup.