2.2 Detection of EVI1 and fusion transcript levels
All patients were collected bone marrow samples at diagnosis. Total RNA was extracted from nucleated cells. Reverse transcription of RNA and TaqMan-based RQ-PCR to measure the EVI1 transcript as well as BCR-ABL1, E2A-PBX1, TEL-AML1 and MLL rearrangement (MLL-AF4, MLL-AF9, MLL-AF1p and MLL-AF1q) fusion transcripts were performed as described in our previous studies.13,21 ABL was selected as the control gene.22 The amplification was performed in duplicate, and the EVI1 transcript level was calculated as EVI1 transcript copies/ABL copies in percentage.