Polymerase chain reaction diagnostic applications

The polymerase chain reaction (PCR), developed by Mullis, is a simple and most effective way of amplifying, i.e. producing multiple copies of, a DNA sequence. It finds applications in all sorts of areas not immediately associated with nucleic acid biochemistry, e.g. genetic screening, medical diagnostics, forensic science, and evolutionary biology. The general public is now well aware of the importance... 

The polymerase chain reaction has numerous applications in basic research, and its use as a diagnostic tool is expanding. The main limitation to the method is that, to synthesize appropriate oligonucleotide primers, the sequence of at least part of the molecule to be amplified must be known beforehand. 

Nucleic acids are also valuable as diagnostic reagents. In combination with the recently developed amplification method, polymerase chain reaction (PCR), nucleic acid probes allow the detection of trace amounts of a specified nucleic acid sequence. Thus, the presence of the DNA of pathogens can be ascertained with great sensitivity and rapidity. Further, these tools permit the analysis and the detection of gene defects in individual patients, and aid in the tailoring of therapeutic strategies. These applications are discussed in Chapter 8. 

Zoh GJ, Melchers WJ, Kopecka H, Jambroes G, van der Poel HJ, Galaraa JM. General primer-mediated polymerase chain reaction for detection of enteroviruses application for diagnostic routine and persistent infections. J Clm Microbiol 1999 30 60-5. 

Saetta A, Agapitos E, Davaris PS. Determination of CMV placentitis Diagnostic application of the polymerase chain reaction. Virchows Arch. 1998 432 159-162. 

As pointed out earlier, microfluidic systems have a wide range of applications, e.g. heat exchange systems for electronic devices [28-31], medical diagnostic and analytical chemical applications [69, 70], and precision dilution systems with minimal dead volume for gas chromatography [71]. More may be anticipated as the technology matures. Current research at many laboratories has shown the need to provide flow control at extremely low levels for sensor-controlled implanted drug delivery systems [72] and portable diagnostic cards for polymerase chain reaction analysis [73]. 

In biomedical diagnostics, the amplification of captured or adsorbed nucleic acids using the classical polymerase chain reaction (PCR) method is one of the aims targeted in various biological applications. The enzymatic amplification of desired nucleic acids is often performed after the desorption or release step. Thanks to hydrophilic, highly hydrated magnetic and non-magnetic latex, direct amplification of adsorbed nucleic acid molecules onto the particles [17] is now possible. 

Lab-on-a-chip devices of this kind, so-called micro-total analysis systems ((xTAS), are textbook examples of how an appropriate reactor design considerably facilitates analyses. These systems benefit from highly efficient heat transfer in different reaction zones, thus allowing for realizing a complete sequence of different reactions within a single reaction channel. It is for these reasons that jtTAS are particularly well suited for nucleic acid analyses by means of the polymerase chain reaction (PCR). Other fields of application comprise molecular diagnostics or forensics [53]. 

---