James D. Watson When, in late March of 1953, Francis Crick and I came to write the first Nature paper describing the double helical structure of the DNA molecule, Francis had wanted to include a lengthy discussion of the genetic implications of a molecule whose struc ture we had divined from a minimum of experimental data and on theoretical argu ments based on physical principles. But I felt that this might be tempting fate, given that we had not yet seen the detailed evidence from King's College. Nevertheless, we reached a compromise and decided to include a sentence that pointed to the biological significance of the molecule's key feature-the complementary pairing of the bases. "It has not escaped our notice," Francis wrote, "that the specific pairing that we have postulated immediately suggests a possible copying mechanism for the genetic material." By May, when we were writing the second Nature paper, I was more confident that the proposed structure was at the very least substantially correct, so that this second paper contains a discussion of molecular self-duplication using templates or molds. We pointed out that, as a consequence of base pairing, a DNA molecule has two chains that are complementary to each other. Each chain could then act ". . . as a template for the formation on itself of a new companion chain, so that eventually we shall have two pairs of chains, where we only had one before" and, moreover, " ...

PCR, developed at Cetus Corporation/USA by Henry A. Erlich, Kary Mullis and Randall K. Saiki, is a very simple method for amplifying nucleic acids in vitro. The realization of this idea bases on the repetition of a set of three different temperatures and yields an increase of the target structure up to a factor of 106 to 1012. Therefore, this technique is predisposed for safe analysis and characterization of DNA and RNA sequences of interest, even where the starting amount of material is enormously small. Because of its sensitivity, speed and versatility this method is particularly suitable for investigations of oncogenes, tumor associated translocations, retroviral sequences, lymphokines and mainly the broad field of degenerative and inflammatory diseases of nervous system. PCR seems to be the technique which could overcome the two most important problems in that field: very small amount of material combined with the necessity of rapid diagnostic procedures in inflammatory infections. "PCR topics" will give an actual overview of basic and applied research fields on usage of polymerase chain reaction. All contributions to this book have been presented at an international congress on "Usage of Polymerase chain reaction in genetic and infectious diseases" which took place in june 1990 in Berlin. The editors wish to thank all participants for their contributions. We offer our thanks and gratitude to our coworkers and especially to our technical assistents Barbara Trampenau, Mirjana Wiirdemann and Hannelore Leonhard.

This indispensable manual is a compilation of review articles written by experts in the field of PCR technology. It is a recommended purchase for all microbiology and molecular biology laboratories and university libraries.

Kary Mullis was awarded a Nobel Prize for inventing the PCR technique more than a decade ago in 1993. Since its "discovery", multiple adaptations and variations of the standard PCR technique have been described. This publication aims to provide the reader with a guide to the standard PCR technique and its many available variants, with particular emphasis being placed on the role of these PCR techniques in the clinical diagnostic laboratory (the central theme of this book).

This is an introduction to the methods and applications of polymerase chain reaction (PCR) technology, a technology developed by Erlich's group at Cetus and Cetus, and is expected to be used in all biology laboratories worldwide within the next few years.

Modern Techniques for Food Authentication, Second Edition presents a comprehensive review of the novel techniques available to authenticate food products, including various spectroscopic technologies, methods based on isotopic analysis and chromatography, and other techniques based on DNA, enzymatic analysis and electrophoresis. This new edition pinpoints research and development trends for those working in research, development and operations in the food industry, giving them readily accessible information on modern food authentication techniques to ensure a safe and authentic food supply. It will also serve as an essential reference source to undergraduate and postgraduate students, and for researchers in universities and research institutions. - Presents emerging imaging techniques that have proven to be powerful, non-destructive tools for food authentication - Includes applications of hyperspectral imaging to reflect the current trend of developments in food imaging technology for each topic area - Provides pixel level visualization techniques needed for fast and effective food sample testing - Contains two new chapters on Imaging Spectroscopic Techniques

Taxonomy is fundamental to understanding the variety of life forms, and exciting expansions in molecular biology are re- volutionising the obtained data. This volume reviews the ma- jor molecular biological techniques that are applied in ta- xonomy. The chapters are arranged in three main sections:1) Overviews of important topics in molecular taxonomy; 2) Case studies of the successful application of molecular methods to taxonomic and evolutionary questions; 3) Protocols for a range of generally applicable methods. The described techni- ques include DNA-DNA hybridization, DNA fingerprinting, RFLP analysis, and PCR sequencing.