Gene Regulation Not Enough in Human Evolution

Getting Even More Circuitous

One of the favorite proof texts for evolution are the genome comparisons between species, in general, and the human-chimpanzee comparison in particular. As the Smithsonian explains:

No matter how the calculation is done, the big point still holds: humans, chimpanzees, and bonobos are more closely related to one another than either is to gorillas or any other primate. From the perspective of this powerful test of biological kinship, humans are not only related to the great apes – we are one. The DNA evidence leaves us with one of the greatest surprises in biology: the wall between human, on the one hand, and ape or animal, on the other, has been breached. The human evolutionary tree is embedded within the great apes.

The evolutionist’s appeal to this genomic evidence is problematic for several reasons. Of course a successful test of a prediction does not mean evolution is true. The claim above that the wall “has been breached” is silly and amounts to the fallacy of affirming the consequent. What is worse, this test has been a failure, not a success, for evolution. There are the identical or near-identical DNA sequences in distant species and the massive genome differences in highly similar species. Both these findings falsified predictions and were shocking to evolutionists.

Beyond these obvious problems which evolutionists, such as at the Smithsonian, ignore, there is the problem that the chimp-human DNA differences do not seem nearly enough to account for the differences between the species. Can a few DNA swaps here and there make a human from an ancient primate? It does not seem likely, so behind this triumphant claim of evolutionists lies a failure to even understand how such evolution could have occurred.

That raises an even more profound problem for evolution. For one idea evolutionists have for how humans may have evolved from an earlier primate is by gene expression. That is, perhaps an important mechanism in evolving humans was not so much modifying the genes, but modifying how much the genes are used, to create proteins.

But this involves a more complicated evolutionary pathway. Instead of DNA mutations that simply modifying genes which create proteins that do a few tasks in the cell, we need DNA mutations that modify how genes are regulated. Such regulation is part of an immense and incredibly complex network, particularly in humans, and it is not at all clear how chance mutations could modify and enhance it.

Recently this story has become even more difficult for evolution as a new study shows that the path from gene expression to protein expression is not as straightforward as was thought. Simply put, the two are not necessarily paired as increasing one, for example, does not necessarily increase the other. As the paper explains:

We found dozens of genes with significant expression differences between species at the mRNA level yet little or no difference in protein expression. Overall, our data suggest that protein expression levels evolve under stronger evolutionary constraint than mRNA levels.

Those genes with significant expression differences between the human and chimp were thought to be important drivers of evolution. Did not the expression level difference between the species occur after they diverged from a common ancestor and was that not part of what created humans (even though we have no idea how)? Now evolutionists are not certain. As one evolutionist explained:

Some of these patterns of mRNA regulation have previously been thought of as evidence of natural selection for important genes in humans, but this can no longer be assumed.

Not only can that no longer be assumed, but the evolutionary mechanisms just became even more complicated. First evolutionists thought humans evolved by mutating genes which create proteins that do a few tasks in the cell. That didn’t work so they added DNA mutations that modify how genes are regulated. Now that is not working so they must add DNA mutations that modify how the expression product (the mRNA transcript) is regulated. So now the evolutionary pathway is even more complicated.