Molecular Markers in Plant Genetics and Biotechnology Molecular Markers in Plant Genetics and Biotechnology Editor Dominique de Vienne Institute National de la Recherche Agronomique Versailles, France % Science Publisher Inc. Enfield (NH), USA Plymouth, UK © 2003, Copyright reserved SCIENCE PUBLISHERS, INC. Post Office Box 699 Enfield, New Hampshire 03748 United States of America Internet site: http://www.scipub.net [email protected] (marketing department) [email protected] (editorial department) [email protected] for all other enquiries) ISBN 13: 978-1-57808-239-9 (hbk) Published by arrangement with INRA, Paris, France. Ourage publie avec le concours du Ministere frarn;ais charge de la culture- Centre national du livre. This work has been published with the help of the French Ministere de la Culture - Centre national du livre. Library of Congress Cataloging-in-Publication Data Marquerurs moleculaires en genetique et biotechnologies vegtales. English. Molecular markers in plant genetics and biotechnology/editor Dominique de Vienne. p. cm Includes bibliographical references (p.). ISBN 1-57808-239-0 1. Plant genome mapping. 2. Genetic polymorphisms. I. Vienne, D. de (Dominique) II Title. QK981.45 M37 2003 52.8'62-dc21 2002036561 Translation of: /es marqueurs moleculaires en genetique et biotechnologies vegetales, !NRA, Paris, 1998. Text updated by author for the English edition in 2002 French edition: ©INRA, Paris, 1998 ISBN 2-7380-07766-7 ISSN 1144-7605 Published by Science Publishers, Inc. Enfield, NH, USA Foreword Does Science progress essentially by the acquisition of new tools or by the emergence of new concepts? This debate between Homo faber and Homo sapiens can be fed with several examples illustrating the relevance of these two points of view and, above all, the dialectic at work between these two sources of rejuvenation of approaches. Those who favour universal attraction, the theory of evolution or general relativity, are opposed to those who emphasize the decisive role of optic instruments (telescopes and microscopes of all types) or analytical tools (mass spectrometry, electro(cid:66) phoresis, magnetic resonance, etc.). In this debate, molecular markers provide a fresh illustration of the key role that new tools can play in reviving scientific fields that are rich, even superabundant, in theoretical concepts but deficient in the capacity for refined observation of their object. Studies in quantitative genetics, as well as in population genetics, have progressively constructed a theoretical apparatus that often allows the explanation of a given fact by several hypotheses that are not mutually exclusive and that are often difficult to organize into a hierarchy. The 'genotype', which these disciplines constantly refer to, can be compared to a puzzle of which one knows only a few pieces and a very fuzzy overall image. It is clear from this analogy that debates on what the image represents could get lively! Now, within a few years, geneticists have been possessed of a significant number of new pieces of the puzzle, and this new deal allows them to discriminate between hypotheses, or perhaps discard them all to construct new ones, illustrating thus the dialectic mentioned above between tool and concept. The technological revolution has been extremely rapid. When DNA fingerprinting in humans was developed in the mid-1980s, many thought that its cost and complexity would limit it to criminology or specific applications. Twenty years later, it is difficult to study the genetics of an animal or plant species, to describe its biodiversity or for genetic improvement, without using molecular markers. This volume, edited by Dominique de Vienne, very clearly presents these different approaches and their fields of application. The challenge was difficult: the techniques are rapidly developing and are often similar, En field(eNH fNH)lH, nU SeNUA PlUlAnd, NUy mniAldoUieiut and the definition of their 'field of relevance' requires a fine understanding of the problems that must be tackled. The authors seem to have succeeded thoroughly. Beyond its technical value, I am sure that this work will impart to the reader the present feverish enthusiasm of geneticists, who are coming closer and closer to revealing the traits of an object that they have long manipulated without really having known: the genome of plant and animal species. Bernard Chevassus-au-Louis Preface The intensive use of molecular markers, even though it does not coincide with the emergence of a new scientific field, completely overturned several scopes in biology in the 1990s. One example is positional cloning, by which a gene with an unknown product can be isolated, just from its position in the genome. But this aspect, which medical genetics has widely advertised, must not obscure other equally fundamental applications. In the field of evolution, comparative mapping allows us to locate the genomic structural alterations that have occurred during the diversification of a genus or family. In formal genetics, the factors that influence the recombination rate can be analysed systematically. In population genetics, diversity and gene flow can be measured. The field most rejuvenated by molecular markers is quantitative genetics. Considered at first a "science for engineers", because it was used more by plant and animal breeders than by researchers, it is today successful in areas ranging from the analysis of genetic bases of morphological variation to the development of strategies for characterizing "quantitative" genes (the well-known QTL, for quantitative trait loci), and marker-assisted selection has become a powerful tool for plant and animal improvement. The recent complete genome sequencing of two model species, Arabidopsis (a dicot) and rice (a monocot) will greatly increase the potential of marker approaches in all higher plants, due to gene homology and synteny conservation in the plant kingdom. To the extent that the set of methods known as 'molecular markers' apply to widely varying fields in genetics and plant biotechnology, it has not been possible to present the fundamentals of all the fields concerned. In each case we have wanted to show what specific inputs markers offer, the new questions they enable us to resolve, and possibly the problems they raise. The reader will need to refer, wherever necessary, to the fundamental works in genetics (formal, quantitative, or population genetics). Sound notions of molecular biology and statistics will also be useful. One exception is nevertheless made for the construction of genetic maps, the theory of which has been detailed for two reasons. First, the maps are the basis of most applications of markers; inadequate knowledge of their nature and way of construction would limit the reader's understanding of the rest of the book. Second, even though their principles have been well Ennn field(eNH fNH)lH, nU SeNUA PlUlAnd, NUy mniAldoUieiut understood for 70 years, their teaching at the university level has been limited for decades for lack of new applications. Finally, the use of informatics offers new perspectives that merit attention. The book is thus organized in the following manner. The first chapter details the different techniques of molecular markers, emphasizing genetic aspects, because these determine the type of use one can put it to. The construction of genetic linkage maps is the subject of the second chapter, where the advantages and disadvantages of the most common mapping populations are specified. The particular case of mapping of major genes, especially for the purpose of positional cloning, is addressed in the third chapter. Detection and applications of QTL controlling the expression of quantitative traits are presented in the fourth chapter, which also tackles the complex question of their identification. The fifth chapter underscores the major contribution of molecular markers in analysis of the structure and evolution of natural populations. Finally, the advantages of markers in selection, for studies of diversity and in the context of marker-assisted selection, are discussed in the last chapter. Throughout the book we have tried not only to expose in detail the principle of the numerous possibilities offered by markers, but also to illustrate them systematically with relevant bibliographical results. We have sought to give some unity to the work while respecting the spirit of each chapter, which is determined by the personality of the authors as well as the specificity of the field explored. We hope that the work will therefore answer the needs of students as well as teachers, and that it will be a valuable tool for all researchers using markers, no matter what their objectives are. Dominique de Vienne Contents Foreword v Preface vii Introduction 1 Definitions 1 What is a 'good' genetic marker? 1. Principal sources of molecular markers 3 D. de Vienne, S. Santoni and M. Falque Criteria of classification 3 Codominant markers detected individually 4 Sequence polymorphism 4 Differences at restriction enzyme sites: the RFLP technique 5 A particular case of RFLP: CAPS 15 Differences of conformation: SSCP 17 Differences of stability: D/TGGE 17 SNP genotyping techniques 19 Polymorphism of number of sequence repeats: SSR 29 Patterns of multiple dominant markers: genetic fingerprinting 31 Sequence polymorphism 31 Differences in hybridization sites of an arbitrary primer, or techniques of MAAP, RAPD, AP-PCR and DAF 31 Differences of restriction sites and hybridization sites of specific primers: AFLP™ 35 Polymorphism of number of tandem repeats 37 ISSR techniques 37 Minisatellites 38 Gene markers: cDNA and proteins 39 What markers are suitable for what purpose? 39 Glossary 41 2. Construction of genetic linkage maps 47 D. de Vienne The concept of genetic distance 48 The Haldane distance 49