Figure 5. External standards mixture controls for inter-experimental variation in fluor signal or quantification cycle (Cq) selection.

(A–D) Effect of diluting labeled probe with unlabeled probe on measurement of MYC in benign, non-FFPE lung cDNA reverse transcribed with gene specific primers (triplicate measurements, with error bars). (A, B) NT labeled probe diluted with NT unlabeled probe. (C, D) IS labeled probe diluted with IS unlabeled probe. (E) Effect of inter-day variation in threshold selection on measurement of MYC and ACTB in surgically removed, FFPE sample 8 (SM8). NT: native template. IS: internal standard. FFPE: formalin-fixed, paraffin-embedded. The asterisk (*) indicates that Cq values were undetermined by software.