COLORIMETRIC DETECTION OF COMPETITIVE PCR PRODUCTS FOR QUANTIFCATION OF HEPATITIS-C VIREMIA

A method based on competitive polymerase chain reaction (PC R) and col orimetric detection of the amplified products was developed to quantif y hepatitis C virus (HCV) genomes. Serum samples were obtained from pa tients who were treated with interferon alpha (IFN-alpha). After rever se transcription of the HCV RNA, the cDNA was coamplified with a seria lly diluted cloned HCV competitor DNA using nested PCR. The competitor DNA consisted of the amplified region of the wild type HCV cDNA with an internal region substituted with the lac operator (lacO) sequence. The PCR products were quantitated specifically by a colorimetric solid -phase assay. The results suggest that the method is well suited for a nalysing the kinetics of the anti-HCV effects during IFN-alpha treatme nt. The quantification assay is simple, reliable and suitable for quan titating HCV genomes in a large number of clinical samples.