I’ve just finished reading Evolution after Gene Duplication, which was edited by Katharina Dittmar and David Liberles and released in 2010. Before I bought the book I struggled in vain to find a review, so thought I would attempt to provide one here. However, before opining on the book itself, it’s worth a brief look at the value of writing and reading such a book.
In 1970, Susumu Ohno famously dubbed gene duplication “the major force of evolution”. By his own admission, this statement was made “on the basis of the scant evidence available”; but the technological advances of the subsequent 43 years have provided the means to test some of his revolutionary hypotheses, and extend our knowledge of evolution by gene duplication. In their book, Dittmar and Liberles catalogue work from a wide range of fields, and at each stage highlight the improvements these studies have made to our understanding of the evolution of gene duplicates.
The book starts with chapters that describe in a broad sense the evolution and divergence of gene duplicates, and the factors governing their retention. It then moves on to the specifics of the mechanistic basis of duplication, before a series of chapters explore how duplication can be studied using mathematical models, phylogenetics and systems biology. The final three chapters each consider a different case study: birds, plants, and vertebrates.
This may sound like a lot of topics to cover in one book, but far from skimming over their surface, each is treated in enough depth to warrant inclusion. Indeed, I found one of the best aspects of the book to be that duplication is considered in its full context. This served to broaden my outlook on gene duplication, and also provided an accessible introduction to the methods used in these studies.
Another valuable addition are the chapters which explore aspects of gene duplication that are often little-considered or taken for granted, such as redundancy (is it ever selectively advantageous?) and the cost of duplication (what is the size and nature of this cost?). Both of these sections (by Ran Kafri & Tzachi Pilpel and Andreas Wagner, respectively) do an excellent job in laying out the evidence for the competing hypotheses, as well as extending the ideas with their own thoughts.
An outstanding chapter was “Myths and Realities of Gene Duplication”, by Austin Hughes and Robert Friedman. Here the authors pull no punches:
“The proliferation of numerous ill-founded statistical methods has given rise to a kind of “computer-assisted storytelling” that purports to test hypotheses but in fact does not adequately consider alternatives.”
They challenge some ideas that were first proposed by Ohno forty years ago, and have become almost canonical since, such as “The Polyploidization Obsession” (their term). Their dissection of the logical basis and evidence for these ideas makes for refreshing and stimulating reading.
If I had one small gripe, it would be each chapter’s retreading of basic concepts, such as the established evolutionary paths for duplicates (retention, subfunctionalization, neofunctionalization & pseudogenization); however, this is unavoidable in any book that assimilates contributions from so many authors in so many fields. The repeated treatment of these concepts does at least serve as a barometer for each author’s opinion on such integral ideas.
I would highly recommend Evolution after Gene Duplication. Its breadth of topic and depth of detailed thought make it a valuable book.
Dittmar, K. & Liberles, D. (2010) Evolution after Gene Duplication. Wiley-Blackwell.
Ohno, S. (1970) Evolution by Gene Duplication. Springer-Verlag.