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MOLECULAR PARASITES. "But most of the 90 percent consists of DNA sequences called transposons. Occupying fully half the human genome, transposons are stretches of DNA that can hop around in host DNA. They are somewhat related to viruses, and Sean Eddy...calls them “molecular parasites.” https://www.geneticliteracyproject.org/2014/08/05/how-much-of-human-dna-is-doing-something/ View in LinkedIn

RESIDUAL DNA. "So what’s the other 90 percent of the human genome up to? It has been called junk, and although scientists don’t much like that term, junk is what a lot of it appears to be. Some of that DNA, for instance, is leftover fragments of dead viruses that invaded our ancestors’ genomes aeons ago." https://www.geneticliteracyproject.org/2014/08/05/how-much-of-human-dna-is-doing-something/ View in LinkedIn

NEUTRAL DNA. "The rest of the genome, Birney said in 2012, is not–as some would have it — just biological “noise.” He prefers to call that DNA “biologically neutral,” meaning “that there are totally reproducible, cell-type-specific biochemical events that natural selection does not care about." https://www.geneticliteracyproject.org/2014/08/05/how-much-of-human-dna-is-doing-something/ View in LinkedIn

BIG SURPRISE. "The 8% is nearly all regulatory sequences, DNA that governs the behavior of the 1 percent of DNA that codes for proteins...until the ENCODE project, scientists thought regulatory sequences would take up about the same amount of space as protein-coding sequences. It was a big surprise to learn that the DNA that regulates genes was eight times bigger." https://www.geneticliteracyproject.org/2014/08/05/how-much-of-human-dna-is-doing-something/ View in LinkedIn

GETTING SETTLED. "Add the exons — exons are the sequences that specify the code for making the proteins that carry out our bodily functions — and that pushes the percentage of “functional” sequences up to 9 percent, which is pretty close to 8.2 percent. (Yes, it is an astonishing fact that protein-coding sequences, which are what we mostly mean when we say “genes,” occupy only a little over 1% of the human genome.)" https://www.geneticliteracyproject.org/2014/08/05/how-much-of-human-dna-is-doing-something/ View in LinkedIn

OXFORD AND ENCODE TO AGREE. "They believe the ENCODE folks would largely agree. “We don’t think our figure is actually too different from what you would get looking at ENCODE’s bank of data using the same definition for functional DNA,” says joint senior author Chris Ponting of the MRC Functional Genomics Unit at Oxford." https://www.geneticliteracyproject.org/2014/08/05/how-much-of-human-dna-is-doing-something/ View in LinkedIn

THE REAL MESSAGE. "The Oxford researchers are saying that only a small proportion of our genome, less than a tenth, is so crucial to our existence that natural selection weeds out injurious mutations and works hard to keep it mostly intact." https://www.geneticliteracyproject.org/2014/08/05/how-much-of-human-dna-is-doing-something/ View in LinkedIn

BOTH AND? " Who’s correct? It’s possible–in fact, it’s likely–that both groups are. It depends on what is meant by the word “functional.” The explanation seems to be that, while some 80 percent of our DNA is doing stuff, less than 10 percent of it is doing such important stuff that natural selection has preserved it largely intact in the mammal line for 100 million years. (Anatomically modern humans — that’s all 7 billion of us, the last Homo standing — have only been around for a couple of hundred thousand years.)" https://www.geneticliteracyproject.org/2014/08/05/how-much-of-human-dna-is-doing-something/ View in LinkedIn

PARTIAL ANSWER. "Even the ENCODE project, looked at a relatively small number of cell types. There are many transient progenitor cell populations whose epigentic marks are not yet described. So I really would not waste much thought about whether it is 8% or 80% functional. I would say there is likely to be remnants of DNA from transposons, gene duplications, pseudogenes etc. But how much of this is truly non-functional remains unknown." https://lnkd.in/e_se8kz View in LinkedIn

8.2% OR 80% FUNCTIONAL? "We do not know enough about gene regulation, epigentic imprinting, and chromatin dynamics to even say how much of the genome is superfluous. I would venture to guess that much of the genome is designed to regulate the complex processes of cell-type specific gene expression and embryonic development." https://lnkd.in/e_se8kz View in LinkedIn