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Hank brings us breaking news from a team of geneticists working on figuring out what all that "junk DNA" in the human genome really is - turns out it's not junk after all.

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[intro music]

Hello and welcome back to the membrane-enclosed nucleus that is my office, where today I'm going to tell you what the garbage inside you is really worth.  And I don't mean the Hot Wheels tire that you stuck up your nose as a kid or the Slim Jim that you ate last week that's, you know, still in there; I'm talking about your junk DNA.

A few weeks ago, we posted a Dose about the Human Genome Project, the years-long effort to decode the information contained in our genes.  In case you haven't seen it yet, one of the project's most surprising findings was that only 2% of our genome actually contains genetic code, that is, instructions for making the proteins that make us, us.

To figure out what the frick the rest, the junk DNA, is for, another effort has mustered the brain power of more than 440 scientists in 32 labs around the world.  They call themselves the Encyclopedia of DNA Elements, or the ENCODE Project, and today, they released some of their findings, which, while kind of weird, could change the future of biomedical research.

The first, and probably best news, is that about 80% of your genome isn't junk after all; it contains sequences that play a role in at least one function in one kind of cell throughout your lifetime.  They could just be there to be copied or to bound to by a special molecule, but the point is they do something.

But maybe more importantly, the team also found about 20% of the human genome consists of regulatory genes.  These are genes that don't actually make any of the stuff in you; instead, they're in charge of activating or deactivating those genes that do the nitty gritty building of your body.  These regulators working together have been described as a giant control panel containing some 4 million genetic switches that determines which of your genes are put to work, and when, and where.  Adding to the intrigue, in any given cell, an average of only 200,000 of these 4 million switches seem to have been turned on, meaning that they've actually activated their component genes.  And many of the regulators appear nowhere near the genes that they regulate.

So clearly we have a lot more to learn.  But already the discovery is having sweeping implications for the world of medicine.  One ENCODE team studied 349 tissue samples taken from all the major human organs, and they found that more than 200 common diseases are caused by changes to those regulatory genes and not to the genes that actually make the parts that become diseased.
For example, a whole host of autoimmune diseases, like asthma, Crohn's disease, lupus, MS, and ulcerative colitis, which I have, stem from changes in the regulatory genes that effect the immune system.
Meanwhile, variations in genes that regulate insulin production have been linked to Type I diabetes.

All this may totally change how we predict and treat illness, which is fantastic, especially for those of us who have diseases that may be caused by this stuff.

But it's also exciting because we still don't know what all that other junk does.  It's an exciting time to be researching genes, and for that matter, to be having them.

So be sure to keep watching SciShow News; if you have any questions or comments or ideas you can leave them in the comments below, or on Facebook or Twitter, and we'll see you next time.