Determination of Cytochrome P450 2D6 (CYP2D6) Gene Copy Number by Real-Time Quantitative PCR

摘要

Gene dosage by real-time quantitative PCR has proved to be accuratefor measuring gene copy number. The aim of this study was to applythis approach to the CYP2D6 gene to allow forrapididentification of poor and ultrarapid metabolizers (0, 1, ormore than2 gene copy number). Using the 2−ΔΔCtcalculation method and a duplex reaction, the number of CYP2D6gene copies was determined. Quantitative PCR was performed on 43samples previously analyzed by Southern blotting and long PCRincluding 20 samples with a heterozygous deletion, 11 with normalcopy number (2 copies), and 12 samples with duplicatedgenes. Theaverage ratio ranged from 1.02 to 1.28, 1.85 to 2.21,and 2.55 to 3.30, respectively, for the samples with 1 copy, 2copies, and 3 copies. This study shows that this method issensitive enough to detect either a heterozygous gene deletion orduplication.