Representative pattern of residual disease found in patients tested early after SCT, at relapse and post-DLI. One of 3 patients tested, all with similar patterns, is shown. On the x-axis are months post–stem cell transplantation (SCT). The results of the quantitation of BCR-ABL transcripts (■) are expressed as the ratio of BCR-ABL to ABL mRNA (y-axis, in a logarithmic scale). The results of the RQ-PCR for gBCR-ABL are represented as diamonds: ♦, gBCR-ABL–positive; ◆, gBCR-ABL–negative. gBCR-ABL was detected in a transcript-negative sample prerelapse and at relapse; after donor lymphocyte infusion (DLI), a transcript-negative sample was gBCR-ABL–positive; later samples were gBCR-ABL–negative.