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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

OXFORD DEFINITION. "The Oxford researchers want to count as “functional” only DNA involved in shaping a person’s body and behavior–the phenotype, DNA that is acted upon by natural selection." https://lnkd.in/eExYi3R View in LinkedIn

PHAGES. "Like all viruses, phages are metabolically inert in their extracellular form (the “virion”), and they reproduce by insinuating themselves into the metabolism of the host. The mechanisms by which phage virions infect their host cells...vary among the different types of phages, but they all result in delivery of the phage genome into the cytoplasm of the bacterial host, where it interacts with the cellular machinery to carry the phage life cycle forward." https://lnkd.in/eBxpUF7 View in LinkedIn

ONLY 8.2% FUNCTIONAL? " From extrapolations we estimate that 8.2% (7.1–9.2%) of the human genome is presently subject to negative selection and thus is likely to be functional. Nearly 99% of the human genome does not encode proteins, and while there recently has been extensive biochemical annotation of the remaining noncoding fraction, it remains unclear whether or not the bulk of these DNA sequences have important functional roles." (Oxford study). https://lnkd.in/eMD6XXb View in LinkedIn