New genes from non-coding sequence: the role of de novo protein-coding genes in eukaryotic evolutionary innovation
The origin of novel protein-coding genes de novo was once considered so improbable as to be impossible. In less than a decade, and especially in the last five years, this view has been overturned by extensive evidence from diverse eukaryotic lineages. There is now evidence that this mechanism has contributed a significant number of genes to genomes of organisms as diverse as Saccharomyces, Drosophila, Plasmodium, Arabidopisis and human. From simple beginnings, these genes have in some instances acquired complex structure, regulated expression and important functional roles. New genes are often thought of as dispensable late additions; however, some recent de novo genes in human can play a role in disease. Rather than an extremely rare occurrence, it is now evident that there is a relatively constant trickle of proto-genes released into the testing ground of natural selection. It is currently unknown whether de novo genes arise primarily through an ‘RNA-first’ or ‘ORF-first’ pathway. Either way, evolutionary tinkering with this pool of genetic potential may have been a significant player in the origins of lineage-specific traits and adaptations.
De novo genes are usually defined as protein-coding genes that have evolved from scratch from previously non-coding DNA.
De novo genes are not only important for their functional and biological contribution to the lineages in which they originate; they are also very informative in terms of our growing understanding of the evolution the genome and of new gene functions. Evolution continues to tinker.
My comment: If you define de novo genes in the context of their evolution from scratch, you have no choice but to tout the pseudoscientific nonsense about neo-Darwinism that you were taught to believe in.
For contrast: The de novo creation of experience-dependent olfactory receptor genes links atoms to ecosystems via the conserved molecular mechanisms of nutrient-dependent RNA-mediated protein folding chemistry.
See also: Search Results for ‘de novo creation’