Epigenetics: Linking Genotype and Phenotype in Development and Evolution
Hallgrimsson B and BK Hall, eds. 2011. Epigenetics: Linking Genotype and Phenotype in Development and Evolution. University of California Press. 472 pp. ISBN: 978-0520267091
M Alonzo, BA Armfield, J Atallah, AS Beedle, T Buklijas, LN Cooper, SF Foster, TA Franz-Odendaal, PD Gluckman, R Gorelick, J Griesemer, C Grunau, BK Hall, B Hallgrimsson, TF Hansen, MA Hanson, SW Herring, B Kablr, MI Kirby, C Kovach, EW Larsen, M Laubichler, DE Lieberman, V Lloyd, FM Low, R Massicotte, P Mattar, LA MEachern, A Minelli, C Neufield, L Olsson, AR Palmer, CJ Percival, JT Richtsmeier, C Schuurmans, KK Smith, DL Swiderski, JGM Thewissen, MA Wund, ML Zelditch
In the first sentence, the editors define epigenetics as “the study of emergent properties in the origin of the phenotype in development and in modification of phenotypes in evolution.” In other words, traits or processes are epigenetic if they arise from interactions occurring above (epi) the level of the DNA sequence. Necessarily, this means that epigenetics can occur at many levels (gene to individual), and this broad approach is reflected in the scope of this volume. The editors begin with an introduction to the volume, where they present their broad definition and approach and briefly describe the content of the book. They point out that the volume explores many different systems and contexts in order to demonstrate the central role and explanatory power of epigenetics. The first part (chapters 2 and 3) focuses on the historical and philosophical foundations of the concept and its relevanve to evolutionary studies. The second part (chapters 4-8) highlights varied approaches to the study of epigenetics (e.g. genetic imprinting, methylation, emergent properties in development). The third part (chapters 9-15) focuses on the epigenetics of vertebrate organ development, presenting a series of case studies that demonstrate the importance of this phenomenon. These include the role of chromatin modification in neural development, the self-organization of tissues, epigenetic interactions in the cardiac neural crest, epigenetic processes affecting osteogenesis, the epigenetic role of muscle-bone interactions, interactions in the developing limb. The final part (chapters 16-23) will be of greatest interest to the JHE readership, as presents a series of chapters that use epigenetic frameworks to understand organismal evolution and dysmorphology. This includes a chapter by Lieberman on the importance of epigenetic mechanisms in determining cranial variation and shape, with specific reference to cranial shape change in human evolution. Other chapters focus on the epigenetic basis of phenotypic plasticity, and the adaptive significance (or not) of epigenetic processes. Two final chapters then look at the role of epigenetic mechanisms in cranial dysmorphology and disease. The volume is bookended by a summary chapter by the editors looking at the role of epigenetics at varied levels (gene, cellular, tissue, organ, individual). A valuable volume for anyone interested in the emergent properties that help link the genotype to the phenotype.