The creationists were more circumspect. Perhaps gene coding DNA was a small component of the genome but, they protested, all that DNA is there for a reason. We are designed and we are very complicated. Our lack of knowledge does not preclude that the rest of the DNA is functional, we just aren't finished looking. So the junk DNA scenario was disputed by creationists decades ago. Pseudogenes, they said, probably had a function and were not left over relics from our primate, mammalian or reptilian past. Other codes beyond the triplet codon to amino acid likely existed.
This week Nature published 6 papers of several they aim to publish on the ENCODE project, along with other related material at their site.
The publication has made this news though much of this kind of information has been known to several researchers. The importance of introns has been known for some time. That polymerases produce far more RNA than is translated into protein is documented, even if the reason the this has been elusive. Gene regulators and promoters have been known of for decades, though it turns out that enhancers do not exist solely adjacent to the gene, but at distances of hundreds of thousands of bases distant. Why? Well because the 3 dimensional configuration of DNA means that a distant "file" location may happen to be physically nearby.
Interestingly the design advocates were long claiming unknown function for junk DNA. After all, while a few mutations have accumulated since creation, 95% of our genome housing junk is not consistent with design, even broken design. Creationists were dismissed, but it turns out they were correct all along. And the evolutionists who insisted that our genome was predominantly junk are left looking the fool. So much for the off quoted adage,
Nothing in biology makes sense except in the light of evolution.Though I don't expect them to be questioning their dogma soon, rather adding some evolutionary spin,
Why evolution would maintain large amounts of 'useless' DNA had remained a mystery, and seemed wasteful. It turns out, however, that there are good reasons to keep this DNA.
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