Organisms Viewed from Real Space and Sequence Space

Biology has a very long history. In the process, much research has been conducted on the classification of organisms, the discovery of microorganisms, and the structural analysis of biological macromolecules. Furthermore, in the twenty-first century, it has become possible to analyze the genome sequences of all living organisms. Since the genome sequence contains all the genes of an organism, it is now possible to select research targets from all genes and proteins. The impact of this genome sequence analysis has been significant and has greatly advanced the bottom-up approach to biology. In Chap. 1 , we discuss the history of genome analysis and the impact of genome sequences on biology. We also discuss how genome sequencing has enabled not only the traditional bottom-up approach but also the top-down approach in biological sciences. This is because whole-genome sequences contain significant implications that have yet to be elucidated.