Genetics and Philosophy: An Introduction Paul Griffiths and Karola Stotz, Cambridge University Press, Cambridge, UK, 2013, 270 p., ISBN 978‐1‐107‐00212‐8 (hardback), ISBN 978‐0‐521‐17390‐2 (paperback), £17.99 (paperback), £50.00 (hardback).

This slim volume (228 text pages) is identified in the Cambridge University Press website as a textbook, although that is not explicitly stated by the authors. What they do say in the Introduction (Chapter 1) is “Unlike most books which combine philosophy and genetics in their titles, this is not a discussion of the ethical, legal, and social implications of science. It is a contribution to the philosophy of science, the branch of epistomology (theory of knowledge) which sets out to understand how science works.” A primary goal of this book is to define the gene, particularly in light of developments of the past 40 years or so, in which molecular biology has expanded our earlier concept of the gene as stretches of DNA nucleotide sequences specifying protein amino sequences in linear and uninterrupted fashion. Discoveries about RNA splicing, alternative splicing, chromatin remodeling, assembly of eukaryotic transcription complexes, and epigenetic mechanisms have forced a rethinking of the concept of a gene. Because this review will probably be read more by biologists and biochemists than by philosophers, I will focus my remarks upon sections that would be most helpful to biologists. The first chapter past the introduction (Chapter 2) is entitled “Mendel's gene.” I found this chapter to be a readable account of the history of classical genetics, and it reminded me why I enjoyed my undergraduate course in genetics some years ago. Chapter 3, “The material gene,” identifies the structural nature of the gene and concludes, “Molecular genetics did not reduce or replace Mendelian genetics, but enriched genetics with another way of thinking about genes.” The chapter covers a lot of ground but is rushed and contains several errors, including an aminoacyl-tRNA molecule in Figure 3.3 that is identified as mRNA. Later (page 96) the ribosome is called a ribozyme, which it is, of course, but not in this context—all of which suggests that a student using this book should have one of the contemporary cell and molecular biology textbooks at hand. Chapter 4, “The reactive genome,” deals with the ways in which our concept of the gene had to change with completion of the Human Genome Project, the encyclopedia of DNA elements (ENCODE) Project, and what we have learned about the complexity of transcriptional regulatory sequences. The existence of vast stretches of transcribed but untranslated DNA, and of the use of a single DNA region to encode multiple proteins through alternative splicing or RNA editing, has required redefinition of the gene. At one point, the authors throw up their hands and suggest, half in jest, that “…genes are simply sequences that have been annotated as genes and whose annotation as such has been accepted by the scientific community.” However, the authors, being philosophers, press on, and in Chapter 5, “Outside the genome,” they discuss quite cogently epigenetics, histone modifications, long noncoding RNAs, and RNA interference. I found this chapter to be readable and up to date. The authors move into the nature/nurture issue with a brief discussion of the brown cowbird, which is hatched into an alien nest because of the nest parasitic nature of the parents. How do the young cowbirds learn cowbird behavior? How do they learn to recognize their own species? Is behavior genetically programmed? The book is enriched with many biological examples such as this one. In Chapter 6, “The gene as information,” the authors rush past the noncontroversial genetic code as information, to ask whether genetic information has “meaning,” leading to a discussion of information theory. In the end they conclude, “the only real semantic sense in which the genes carry information is in their role in templating for gene products.” A reductionist conclusion, but I was pleased at the final statement in the book, “…at least for a book in the philosophy of science, research in the molecular biosciences is both strongly reductionist and strongly integrative.” Chapter 7, “The behavioral gene,” deals with the extent to which genes control behavior. Much of this chapter is a discussion of quantitative genetics, essential if one is to deal with questions relating the relative influence of genetics and environment upon behavioral traits. Chapter 8, “The evolving genome,” begins with Dobzhansky's famous statement, “Nothing in biology makes sense except in the light of evolution,” then moves on to a less famous inversion of that statement by Sarkar, “…much of the received framework of evolution makes no sense in light of molecular biology.” The authors delve into “evo-devo” (evolutionary developmental biology) and “eco-devo” (ecological developmental biology) to ask whether interaction between development and the environment has any evolutionary significance. They conclude that if so, the answer must be written in the genes. A brief concluding chapter discusses four major conclusions reached by the authors, including the welcome statement that molecular biology is at least partly integrative. Although this is not a book that I would pick up and read for fun, I did enjoy learning something about how philosophers regard our science. Finally, a strength of the book is a well annotated and up-to-date reference list. Christopher K. Mathews Department of Biochemistry and Biophysics Oregon State University Corvallis, Oregon 97331-7305