Is gene duplication a viable explanation for the origination of biological information and complexity?

Abstract

All life depends on the biological information encoded in DNA with which to synthesize and regulate various peptide sequences required by an organism's cells. Hence, an evolutionary model accounting for the diversity of life needs to demonstrate how novel exonic regions that code for distinctly different functions can emerge. Natural selection tends to conserve the basic functionality, sequence, and size of genes and, although beneficial and adaptive changes are possible, these serve only to improve or adjust the existing type. However, gene duplication allows for a respite in selection and so can provide a molecular substrate for the development of biochemical innovation. Reference is made here to several well-known examples of gene duplication, and the major means of resulting evolutionary divergence, to examine the plausibility of this assumption. The totality of the evidence reveals that, although duplication can and does facilitate important adaptations by tinkering with existing compounds, molecular evolution is nonetheless constrained in each and every case. Therefore, although the process of gene duplication and subsequent random mutation has certainly contributed to the size and diversity of the genome, it is alone insufficient in explaining the origination of the highly complex information pertinent to the essential functioning of living organisms. © 2011 Wiley Periodicals, Inc. Complexity, 2011