Genetic Loss Is Evolutions Gain
Three scientists in the University of California system found that “Repression and loss of gene expression outpaces activation and gain” among recently duplicated genes. Surprisingly, publishing in PNAS,1 they claim the non-intuitive hypothesis that this the mother of evolutionary invention. From the abstract:
Evolutionists widely acknowledge that regulatory genetic changes are of paramount importance for morphological and genomic evolution. Nevertheless, mechanistic complexity and a paucity of data from nonmodel organisms have prevented testing and quantifying universal hypotheses about the macroevolution of gene regulatory mechanisms. Here, we use a phylogenetic approach to provide a quantitative demonstration of a previously hypothesized trend, whereby the evolutionary rate of repression or loss of gene expression regions is significantly higher than the rate of activation or gain. Such a trend is expected based on case studies in regulatory evolution and under models of molecular evolution where duplicated genes lose duplicated expression patterns in a complementary fashion. The trend is important because repression of gene expression is a hypothesized mechanism for the origin of evolutionarily novel morphologies through specialization.
They found that the repression rate of genes is at least twice that of gene activation. They assume that duplicated genes will go their separate ways, and even if down-regulated by the trend toward loss, may undergo “subfunctionalization” – i.e., come up with novel means of achieving function separate from that of the original genes (see 10/24/2003). This begs the question of how the original functions arose. Nowhere in the paper do they explain how novelty can arise, or has arisen, that produces complex function, except to speculate that animal limbs and fly halteres arose through duplication and subfunctionalization.
The question of original function and expression, though, is still apt: “Overall, our results raise an important question: If gene expression regions are more commonly lost than gained, why is all gene expression not eventually lost over evolutionary time?” They surmise that the total expression rate will be constant through the copies; the activation event will have a common ancestry, though two repression events may occur in the daughter genes. How, though, can this create novelty? They do not explain how. They only speculate that since loss occurs, it must be another tool in the evolutionary toolkit: “…our results highlight the fact that because genes and their expression domains duplicate commonly, they must also be lost commonly. As such, the patterns of loss may be as important as gain in dictating the evolution of genomes and phenotypes.” More research will be required, they admit, to see if this is the case.
If this still seems like getting something for nothing, it all comes together in the last paragraph:
In summary, an emerging theme in evolutionary genomics is that loss is a major factor in evolution. For example, gene duplication is quite common, and the fate of most duplicated genes is loss. At least in several cases, DNA loss may be related to a mutational bias, where deletion mutations outnumber insertion mutations. Here we present strong statistical support for a similar loss hypothesis for the evolution of discrete regions of gene expression. Our data were chosen without respect to the hypothesis at hand but represents rapidly duplicating genes, which may have higher rates of expression domain loss. Nevertheless, the methods introduced here are general and could be used to test the hypothesis in future studies by using more data from any species or multiple species. Our results support the idea that gene duplication and loss of discrete, modular expression regions may provide a general mechanism for increased specialization over evolutionary time that may be linked with increases in genomic complexity by gene duplication.
1Todd Oakley et al., “Evolution: Repression and loss of gene expression outpaces activation and gain in recently duplicated fly genes,” Proceedings of the National Academy of Sciences USA, 10.1073/pnas.0600750103, published online before print July 24, 2006.
Folks, it is time to get indignant at the Darwinists. Again. They continue to pull rabbits out of hats with these shenanigans of theirs, their magic words couched in jargon, published in prestigious science journals, trying to make us believe that you can get something for nothing – or worse, that trends toward loss produce gains in complexity and function. This is like believing that shopping centers will emerge from the terrorist rockets landing in Haifa. If such ideas should not become part of the official history of Israel, then neither should this dumb idea become part of the corpus of scientific literature. It only happens because non-Darwinians are disqualified from participating in the discussion. The Darwin Party’s club lounge of tantalizing speculations is making some biologists fat, lazy and corrupt (12/22/2003). Time to unbar the doors and boot the rascals out.
Some things can overcome downhill trends. Fish can swim upstream. Living things can grow against the inexorable law of entropy. Even Jesus said that he who would gain his life must lose it. But all these include intelligently designed mechanisms for harnessing energy against the downhill trend, or intelligent goal-directed behavior. Darwin was supposed to get rid of all that. We can’t let the Darwinian magicians sneak into their bag of tricks things that don’t belong there. It’s like when a Congressman performs voodoo economics to claim his massive pork-barrel project actually saves taxpayers money. With scientists, too, we must demand an accountant and an independent investigator.