Comparative genomics

Abstract

An important hallmark of biological research is the aspect of ‘comparisons’. As the complete genome sequences of numerous organisms have become available, the emphasis in biology has shifted to comparisons at the genome level. Indeed, the last few years have witnessed an exponential rise in the number of organisms whose complete genome has been sequenced, and we are still climbing up the graph. The present article, a primer, explains how one can extract a great deal of information from such analyses that is of great value in our research. The subject of comparative genomics impinges on evolutionary biology and phylogenetic reconstructions of the tree of life, drug discovery programs, function predictions of hypothetical proteins and genes, regulatory motifs and other non-coding DNA motifs, and genome flux and dynamics. Finally the article describes how the information one can extract from a comparative analysis of genomes depends to a large extent, on the specific aspect of the genomes that is being compared and the phylogenetic distances of the organisms involved.