Analysis of patient remission DNA for clonotypicAML1-ETO translocation persistence after treatment.

First, DNA extracted from bone marrow samples was tested for integrity with the use of control gene PCRs (NQO1 and NRASprimers, data not shown). With the same primer sets that were used for screening Guthrie cards, bone marrow samples obtained from treated patients were tested for translocation sequences. All patient samples tested after treatment proved to be positive for clonotypic fusion sequence after 2 rounds of PCR (lanes R). Key to lanes: M indicates marker; D, diagnostic patient–specific DNA; K, Kasumi cell line DNA; H, HL-60 cell line DNA; C, human DNA from a nonpatient control; R, bone marrow sample for patient no. 2 obtained while the patient was on treatment at 5 months after diagnosis; R1, R2, and R3, bone marrow samples from patient no. 3 obtained immediately following induction treatment (2 months after diagnosis), at the end of consolidation (3 months after diagnosis), and 4 months off all therapy (8 months after diagnosis), respectively; RA and RB, DNA from bone marrow from patient no. 4 obtained when the patient was just off all therapy (11 months after diagnosis) and 6 months off all therapy (16 months after diagnosis), respectively.