Quantitative reverse transcriptase PCR (RT-qPCR) of BCR::ABL1 mRNA is a sensitive method for monitoring CML, yet RT-qPCR technical assay variation from lab to lab yielded log fold differences, leading to data that was difficult to interpret from lab to lab [5, 6]. The gene discussed is ABL1; the disease is chronic myelogenous leukemia, BCR-ABL1 positive.