Since the CT value decreases linearly with the increasing amount of plasmid DNA copy number and all of our tested samples (healthy tissue, hyperplasia, adenoma and carcinoma) were located within this linear amplification range (Fig. 4A, B), the copy number of FGFR-2-IIIb and FGFR-2-IIIc transcripts in our test samples could be measured by using the standard curve. This evidence concerns the gene FGFR2 and carcinoma.