Mr. Green Genes
The Art of Genes: How Organisms Make Themselves. Enrico Coen. 386 pp. Oxford University Press, 1999. $35.
Metaphors can be a useful tool for explaining technical nuances to those with backgrounds that differ from our own. Enrico Coen relies heavily on metaphors in The Art of Genes. He uses colors, scents and sensitivities as metaphors for, respectively, regulatory proteins, signaling proteins and receptor proteins. The book continues on a logical course toward explaining how organisms develop, but the metaphors sometimes become clumsy and confuse the point. After the standard background chapters, Coen attempts to describe developmental processes using those same three metaphors: colors, scents and sensitivities.
Although parts of these chapters are interesting, much of the space is spent explaining metaphors; the scientific fact underlying the metaphor is often left undisclosed. Some scientifically naive readers might appreciate this approach, but someone willing to seek out and read 362 pages about developmental biology might want more. A small yet annoying problem must, I assume, be blamed on the publisher. The book relies on the use of "hidden colours" to describe development, yet the entire thing is printed in black and white. Why? Lack of color doesn't ruin the figures, but it certainly takes something away from them.
The strongest chapters deal least with metaphors and instead give real developmental examples. Parts of the second half of the book, where most of the metaphor is left behind, are particularly insightful and should prove interesting to readers of any level. Its major strength is its ongoing description of development as something other than a manufacturing or "cookbook" process:
The process of development is much more like creating an original than manufacturing copies, in the sense that the final product, the adult, is not there from the beginning but gradually emerges through a highly interactive process, in which each step builds on and reacts to what went before in a historically informed manner.
As the author points out in the first chapter and reiterates throughout, this is an incredibly exciting time in developmental biology. The massive mutant screens in various organisms are coming together with molecular trickery and physical manipulations to elucidate how organisms develop. It is a disservice to gloss over the subject by emphasizing metaphors at the expense of the molecular events underlying them. Once the author has gone to the trouble of explaining proteins, DNA, RNA, regulatory genes, promoter sequences, transcription factors, cell-cell communication and a variety of other processes, it seems unnecessary to rely so heavily on metaphor. Metaphors definitely have their place; however, they would be better fitted to short instructive usage rather than as a basis for discussion.—Robert E. Peterson, Zoology, Duke University