Real-time quantitative polymerase chain reaction: A potential tool for genetic analysis in neuropathology

Since its introduction in the early- to mid-1980s, the polymerase chain rea ction (PCR) has been modified and optimized for an increasing number of app lications. Early on, the focus was on the amplification of a specific nucle ic acid template into quantities amenable to identification and experimenta l manipulation. While this remains an important application, recent technol ogy has allowed the use of PCR to accurately quantitate the amount of a spe cific nucleic acid template present in a complex sample. Rather than simply analyzing the final product amount following the course of sequential cycl es of amplification, quantitative PCR allows one to measure the accumulatio n of PCR product during the course of the reaction ("real-time PCR"). Under the appropriate conditions the number of PCR cycles required for the accum ulation of a specific amount of product (during the exponential phase of th e reaction) is a reflection of the relative amount of nucleic acid template present in the sample under analysis. Real-time quantitative PCR allows on e to analyze a relatively large number of samples in a short period of time , potentially allowing multiple markers to be applied on a sample within a time frame consistent with clinical settings. In this overview, we will hig hlight the uses of real-time quantitative PCR as a potential diagnostic too l in neuropathology, focusing on the analysis of CNS tumors.