HUMARA-PCR performed on a mix of FACS-sorted CD3⁺ and CD33⁺ from a patient with CML and 100% Ph⁺ metaphases.

(A) Undigested DNA (left panel) versus HpaII-digested DNA (right panel). The arrows indicate the positions of the 2 alleles. The smaller peaks represent stutter bands that were not included in the calculations. The proportion of CD33⁺ cells was increased from 0% (10:0) to 100% (0:10). (B) RCI values for the respective mixes. The horizontal line indicates an RCI of 3, the limit indicating unbalanced X inactivation (see “Patients, materials, and methods”).