HUMARA analysis and BCR/ABL mRNA expression in mobilized PB in LCP CML. Results are shown for day 1 harvest from UPN 5. HUMARA PCR and BCR/ABL and β-actin RT-PCR reactions were performed as described in Materials and Methods. MNC, CD34⁺HLA-DR⁺, and CD34⁺HLA-DR⁻ progenitors were monoclonal and BCR/ABL mRNA⁺. Shadow bands in the HUMARA PCR are caused by slippage of Taq polymerase. (−), No prior digest withHpaII and Cfo I; (+), prior digest with HpaII and Cfo I.