Junk DNA goodbye!: the battle with Dan Graur continues (Introduction)

by David Turell , Thursday, May 07, 2020, 22:43 (1661 days ago) @ David Turell

A new highly technical article on mutation load negates his arguments:

https://evolutionnews.org/2020/05/paper-shows-that-mutational-load-arguments-dont-refut...

"Perhaps one of ENCODE’s staunchest critics has been Dan Graur, a molecular evolutionary biologist at the University of Houston. He argued in 2017 in the journal Genome, Biology and Evolution that ENCODE’s empirically based conclusions could not possibly be correct because “Mutational load considerations lead to the conclusion that the functional fraction within the human genome cannot exceed 15%.” What exactly is “mutational load”?

"Mutational load is based upon the principal that populations of organisms can only tolerate a certain number of deleterious mutations before they reach a critical level and the population crashes. If every element of a genome is functional, then every possible mutation stands to have a non-neutral effect, and could be potentially deleterious. But if only a small portion of the genome is functional, then most mutations will happen to occur in functionally unimportant regions, and this spreads out mutations in a manner that greatly decreases the likelihood of experiencing a deleterious mutation. Thus, when your genome is filled with “junk,” you can tolerate a much higher “mutational load.”

***

"because now in 2020 serious criticisms have been made of the assumptions in Graur’s “mutational load” arguments. Recently three scientists writing in the journal Genome Biology and Evolution noted that these arguments wrongly assume that there could potentially exist a person with no deleterious mutations in their genome:

"Our approach is different from previous work that compared mean fitness at mutation-selection equilibrium with the fitness of an individual who has no deleterious mutations; we show that such an individual is exceedingly unlikely to exist. We find that the functional fraction is not very likely to be limited substantially by mutational load, and that any such limit, if it exists, depends strongly on the selection coefficients of new deleterious mutations.

"By comparing the population mean fitness at mutation-selection equilibrium to that of an individual who possesses no deleterious mutations, Graur (2017) reached the conclusion that, for likely values of the human per-base deleterious mutation rate, the functional fraction must be small.

***

"We conclude — while making no claims about the actual functional fraction as determined by comparative studies—that a mutational load argument is unlikely to set a low limit on the functional fraction of the human genome, and that any attempt to set such a limit must take into account the fitness effects of new deleterious mutations.

***

"Graur is an eminent scientist — about whom the journal Science said, “Graur’s atheism inflamed his anger at ENCODE.” In an online talk, Graur explained what’s at stake:

"If the human genome is indeed devoid of junk DNA as implied by the ENCODE project, then a long, undirected evolutionary process cannot explain the human genome. If, on the other hand, organisms are designed, then all DNA, or as much as possible, is expected to exhibit function. If ENCODE is right, then evolution is wrong. (my bold)

"He then admits in the talk that his goal is to “Kill ENCODE.”

"Dr. Graur should be commended for his honesty, which makes clear that there’s a lot at stake here. We should not expect ENCODE-critics to go away quietly. But if this latest paper indicates anything, it’s that “mutational load” arguments aren’t the ENCODE-killers that they have been made out to be."

Comment: The 'no junk DNA' is important for atheists to fight as Graur explains. Despite Darwin's later protestations following his first edition that God did it, atheists need his natural evolution theory to stay intact.