Genetic Punk EeK

I recently came across a paper that struck me as interesting in the open access journal BMC Evolutionary Biology. The paper was Which presented data which put me very much in mind of punctuated equilibrium.The paper shows that while duplicated genes are, as had previously been shown, subject to less severe purifying selection subsequent to the duplication the duplicate genes themselves are in fact in the long term subject to greater stabilising selective pressure than genes only occurring once in the genome.Subsequently their model has duplication followed by a brief period of increased tolerance to mutation and subsequent long spans of careful maintenance. Biologically important genes are more likely to have their duplicates retained presumably due to the need to retain the whole functionality of the original, even if it is distributed between two genes.How valid is a comparison between the model in this paper and punctuated equilibrium. Could such a mechanism be related to actual supposedly saltatory changes in gross morphology, I.E, duplications of original ancestral hox genes or even on a larger scale the hox clusters themselves?Am I totally off beam here or are these two apparently similar mechanisms possibly actually connected?TTFN,WK

Thread moved here from the Proposed New Topics forum.

Thread moved here from the Proposed New Topics forum.

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Am I totally off beam here or are these two apparently similar mechanisms possibly actually connected?

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I can think of a couple scenarios that would fit the bill.It is possible that in cases of strong selective pressure to keep duplicates homologous to the original gene that small attenuations in binding and enzyme capacity could slowly change. This kind of action could be analogous to the evolution of the clotting cascade, for instance. This would be escpecially important in small changes that could add up over time, such as small changes in morphology or environmental adaptation.The second scenario would be closer to what many would consider punk-eek. If the duplicate was under very little selective pressure to stay homologous, then the removal of the original through a frame-shift mutation (eg) would suddenly make the organism rely on the duplicate for a similar function. This would be seen as a quick change in phenotype if the original gene was masking the activity or influence of the duplicate. It would be like kicking the chick out of the nest for its first flight. Either it falls on its face or it soars. If this duplicate offered better adaptation over the original, then the gene would spread quickly through the population, especially in a small isolated population.I just skimmed the article, but will look further into it later. Good info.

Punctuated Equilibria is derived from taking allopatric speciation and working out the expected appearance of the fossil record. So there is no obvious connection.

Fair enough, I think that there are still analogous similarities between the two but I admit that I can't really see a case for them being actually functionally related.TTFN,WK