Real-Time PCR to Detect Minimal Residual Disease in Childhood ALL

Measurement of minimal residual leukemia at early time points during therapy has now been shown to predict reliably outcome in childhood acute lymphoblastic leukemia (ALL) (1 -3 ). Consequently, ongoing European treatment protocols are using this technology to stratify therapy. Currently the most widely applicable and sensitive method for the detection of minimal residual disease (MRD) in ALL is polymerase chain reaction (PCR) of antigen receptor gene rearrangements. This technique relies on identification of the leukemia specific junctional sequence from amplification of diagnostic DNA. The sequence is then used either as a clone-specific probe or allele specific primer to detect MRD in DNA taken at times of remission.