In our experiments, we used a multiplex ddPCR assay for p210 BCR–ABL1 Major translocations in the peripheral blood of CML patients, which can quantify the target (BCR–ABL1 Major translocations) and the housekeeping (ABL1) genes in the same well, returning an absolute quantification. The gene discussed is ABL1; the disease is chronic myelogenous leukemia, BCR-ABL1 positive.