I remember my excitement at opening the first edition of Manipulating the Mouse Embryo in 1986. I had just established my own transgenic mouse colony in Boston and was struggling with problematic animal-housing arrangements, cumbersome genotyping techniques and a skeptical reviewer of our first paper on the subject (“this study merely confirms in vivo what the authors have already demonstrated in cell culture”, the curmudgeon wrote). The technology was still in its infancy, and far from routine for an aspiring transcription factor jock like myself, but this book provided detailed instructions on how to address all the burning questions I had about mouse development, and validated my tentative plans to extend my previous studies of gene regulation using recombinant DNA technology. The secrets of mammalian embryogenesis were finally accessible to molecular biology, no matter what my grumpy reviewer thought.
The Year of the Mouse Genome, 2003, is an auspicious launch date for the latest edition of this inspirational laboratory resource. Long regarded as a living bible of mammalian embryonic manipulation techniques, the updated third edition fulfills this mandate. It has been completely reorganized and expanded in the talented hands of the new authors, all leaders in the fields of mouse development and genetic manipulation. Andras Nagy and Marina Gertsenstein have championed chimeric analysis in mouse embryogenesis, and are known for their collective expertise in conditional regulation of the mouse genome. As former head of the mouse transgenic core facility at EMBL, Kristina Vintersten has years of hands-on experience, and is a trusted authority on the nuts and bolts of mouse manipulation. And Richard Behringer, a renowned mouse geneticist,adds his profound knowledge of mammalian development to the mix. It's a great team.
At 764 pages, this tome is half again the size of its predecessor, and is bursting with fascinating concepts and clever techniques. The excellent historical background chapter has been retained and updated, as has the one on mouse development. Chapters covering the basics of transgenic mouse production, embryonic stem cell handling and genetic manipulation have been expanded, and state-of-the-art protocols are presented in an accessible style with more extensive troubleshooting sections. For fields in which significant advances have been made, such as in imprinting, the sections have been extended accordingly. The chapter on chimeras has been broadened and makes the technique seem readily accessible. My lab has never made a chimera but, as I read, I found myself thinking of the many ways I could use this approach.FIG1
An impressive amount of new material has been added as well. Explanatory text and figures reveal the trade secrets of mouse cloning, assisted reproduction strategies (including intracytoplasmic sperm injection and in vitro fertilization) and whole embryo culture systems. Other novel features include DNA electroporation and reporter gene expression in living embryos,the uses of plastic casting to capture morphological anomalies, and other techniques for visualizing gene products, cells, tissues and organ systems. On the molecular side, the section on vector design (Chapter 9) presents the latest conditional and inducible gene strategies, the ins and outs of BAC and YAC cloning, and novel reporters. Although I found the icons used to denote the DNA manipulations too small and hard to follow, an exhaustive array of gene expression tips and pitfalls makes this section a definitive resource and teaching tool. There's even a companion website with supplier links and information, Medline-linked references, and links to other databases of value to scientists working in this field, which has the advantage that supplementary information can be added after the book is published.
Reorganization of the book was necessary, given the amount of new content,and has made this third edition more practical. Easy-to-find references have been collated at the end of each chapter. A glossary of the mouse genome in the second edition was rather inadequate and has been omitted – it's a field in itself by now – and surgical techniques have been grouped together in one very helpful chapter. However, there are some confusing aspects to the new order. Whereas the misleadingly named Chapter 3 (Production of Transgenic and Chimeric Mice: General Issues) is primarily about establishing transgenic mouse colonies, Chapter 7 (Production of Transgenic Mice) is more technical, with important molecular information and detailed protocols. In all fairness to the authors, such a complex package makes it hard to know which should come first, the chicken (sic) or the egg.
There are some practical additions, such as a detailed `how to...' section on setting up your own micromanipulation lab that will be of great value to scientists just starting out, and to established research groups switching to the mouse model. There is also a cautionary appendix that expounds the dangers of hazardous materials used in the protocols. Of particular relevance in this time of exploding mouse colony sizes, escalating animal costs and limiting housing space, when getting mice off the shelf is becoming an increasingly pressing priority, is the section on embryo and gamete cryopreservation and re-derivation. There is even an informative discussion of mouse colony trends(we've come a long way since 1986!).
The book looks classier too. Many of the cartoons, including fate maps of early mouse embryogenesis by the incomparable artist/scientist Rosa Beddington(an original author of this manual, see Fig. 1) have been retained;however, other diagrams have been redrawn to illustrate the techniques more clearly. New colour photographs show real-life results of current genetic strategies. Alas, the old ring-book format is gone, presumably a casualty of the volume's increased girth, but the sturdy spine of the current paper edition will hopefully stand up to the constant thumbing and flattening on the lab bench that have dog-eared my two previous editions.
So what's wrong with this edition? Not much. But well, let's see, there's no heart development in the embryology section. This subject mysteriously didn't rate in the second edition either. Call me biased (alright, I admit I work on heart development), but the lateral mesoderm gives rise to more than the kidneys. The heart is the first organ to form and function in mammalian development, and its prominent and easily visible position during mouse embryogenesis makes it a very helpful signpost.
I would have also liked to see a compendium of protocols listed somewhere in the book, and a bit more cross-referencing would have been useful. For example, Protocol 1 on p. 435 (Electroporating DNA into ES cells and selection methods) is related in subject matter to Protocol 1 on p. 469 (Preparation of ES cells for injection). While we are on the subject of cross-referencing, the index is regrettably uneven. I will forgive the absence of cardiovascular terms (the words heart, cardiogenesis, circulation and vasculogenesis, didn't even make it into the index, and I checked, heart-brokenly). Omission of the term `gene knockout', on the other hand, is a more serious oversight,particularly as none of the chapter headings lead the uninitiated reader to the appropriate pages (knockouts are discussed in Chapter 9, `Vector design for ES cell-based transgenesis and genomic alterations', for those of you who were wondering).
In the greater scheme of things these are trifling concerns, especially considering the breadth of scope and depth of coverage the authors have achieved. I agree with the Cold Spring Harbor Laboratory Press promotional blurb that this book is the “premier authoritative and comprehensive source of technical and theoretical guidance for mouse developmental biologists and geneticists”. It is helpful whether you are tempted to start your own mouse facility, or merely interested in making a single transgenic or knockout animal. It includes a marvelous summary of our current understanding of mouse development, and offers students and teachers alike an updated approach to mammalian genetic manipulation. It is brimming with useful and exciting information for the adventurous postdoc who is ready to embark on the generation of a conditional mutation, and it is a one-stop shop for the seasoned developmental geneticist looking for the latest tricks of the trade. But the best thing about this book is the sense of exuberance that these authors convey about their subject. You can feel their enthusiasm radiating up at you as you read. It is a tremendous time to be a mouse biologist. I am still as excited as I was in 1986.