Tapping into genome secrets

How has genomics changed our view of biology lately? If one focuses on much-discussed rivalries between certain sequencing groups, one could easily argue, 'not much'. But look a little bit closer at what genomic approaches are continuing to produce, and there are clear signs of some profound discoveries in the making. For example, observations from the major sequencing initiatives are beginning to shed light on key aspects of evolutionary divergence, from how functional protein domains have been shuffled and reorganized over evolutionary time to give rise to chordates, to how plants and animals have honed in on similar means, such as the functionally related MADS box and homeobox genes, to reach common developmental ends such as pattern formation. At the same time comparative genomics is giving us new insights into evolution, innovative functional approaches are paving the way to the deeper understanding of specific cellular processes. On one front, gene expression profiles are being integrated with genetic, phylogenetic and biochemical data, allowing regulatory pathways to be expanded and probable function assigned to genetic outliers. Meanwhile on another front, bacterial genomes are being used to map, in space and time, the regulatory circuits from which other diverse cellular systems evolved. As the genome sequencing of a quickly growing list of species continues, it's hard to summarize what the recently completed genomes have taught us — the discoveries they will allow us to make are only beginning to emerge. With DNA providing the informational underpinning for all life, the analysis and comparison of genomes as functional units is proving to be a truly unifying force in biology as it is practised today. Genomic approaches can reveal how a full complement of genetic information is variably exploited by cells undergoing differentiation or unregulated growth, but can also uncover phylogenetic relationships between species and genes, and show how genomes themselves evolve in response to forces that challenge their own fitness. As a set of analytical tools and as a discipline unto itself, the world of genomics is colorful and fast-moving to be sure. Genomics' dizzying pace is spurred on by a set of constant challenges: what information to get, how to get it, and most important, how to use it to answer fundamental questions in biology. Future editions of this column will seek to capture the dynamic way these challenges are being met at different levels of research and in different fields of biology. …