Our “Junk DNA” Is More Important Than We Once Thought

In the search for the genes that make us human, some of the most important answers were hiding not in the genes themselves, but in what was once considered genomic junk.

Thanks to Riley J. Mangan, Ph.D. Candidate, Molecular Genetics and Microbiology, Duke University for his help with this episode!

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Produced by Complexly for PBS Digital Studios

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[mikebauer]

The term “junk” DNA always made me think of the “use 10% of your brain” meme.

[kietdo]

I'm a programmer and I found it very interesting how DNA genes and programming codes work in similar way. If you ever coding something, you know, more than 3/4 of your codes would not create anything (same as non-functional genes), but to ensure the other functional code will work "as expected". We called them "validate codes". Through lot of developments, the size of these validate code keep getting bigger and bigger to the point, they usually take 80 -> 90% of total code size. Funny how junk genes also have characteristic in similar ways.

[TheResidance]

I'm currently doing a master's in biotech and the difference in what we know is staggering. I remember that in my undergrad, it was still called junk DNA. Now, professors are very much "nah, you thought this was going to be easy 😂"

[battleon]

My PhD is on Red-backed Salamanders. They got rid of their lungs and their aquatic life stages and are only a few inches long at most. Despite appearing so simple, they somehow have a genome over 4x as large as ours. It's so big we can't properly sequence it all yet. Even their genome size is just an estimate that differs depending on who you ask.

[WWTormentor]

I got my masters in molecular genetics back in 1994. It’s amazing how far we have come in nearly 30 years. I was recently going through my library of books and found a genetics book. While reading it, it was amazing how complex it was back then, while today it’s just the basics.

[davidtitanium]

I think the "human shares 99% of our dna with chimps" is like looking at two books of completely different size and length and saying they're 99% identical because they use the same paper and have some similar words

[flamencoprof]

I wonder if the appearance of brain and stomach genetic changes at about the same time could be related to the adoption of fire and cooking. That allowed more available calories, which allowed a smaller gut, and also freed up calories allowing a more energy-expensive brain to co-evolve with the smaller gut.

[ArisaemaDracontium]

Having taken college-level biology in the late 90’s, the term “junk DNA” never sat well with me. After watching this, “junk drawer DNA” seem much more appropriate.

[mykstreja]

It's not just in biology that researchers will categorize data that can't be classified as 'junk'. Astronomy, physics, chemistry have all fallen into the trap of lazy thinking.I am heartened that there are those who are willing to face ridicule and investigate the dung heap to find the gem that shows us how much we really don't know.

This video was very informative and well thought out, nothing less than can be expected from PBS.

[luudest]

Please do an episode about what happens at the genetic level when a selective pressure emerges in an ecosystem.

[martinpollard]

As a retired doctor and epidemiologist I love spending time on a whole heap of science topics and this episode crystalised some information I was thinking about and more exactly presented information I did not even have any idea about, so thank you guys.

[dh]

One of the most baffling things to me is how cells know how to differentiate themselves, especially starting from just a single one after the egg has been fertilized.
How cells that contain the exact same DNA manage to perform completely different functions and are able to coordinate themselves to form a complex functioning organism is just fascinating.
If I had to guess, I'd say that the coordination of the expression of the genome requires more information than the sum of all the proteins which are coded within the DNA.
The recipe to make a brick is simple, the art comes from how to sick a bunch of them together to form a building.

[descomunal]

Hidden DNA Potential on shirlest is a treasure trove of insights that everyone should know about. Ever since I read it, I feel like I’ve unlocked a part of myself I didn’t even know existed. Totally worth your time!

[nariutimes]

In my college experience in human development (I graduated in 2013) we would muse that "junk" DNA must have a purpose because humans were way too complex for genes coding proteins to explain such variation. Lovely to see the growth in the field.

[acanuck]

This video was very impressive (all the more so for helping to address a nagging uncertainty I'd long felt about the entire concept of "junk DNA"). BTW, yours was the first presentation to help me understand the difference between "genes" and "DNA writ large". Thank you.

[RodneyG]

The part of my brain that should of been a sociologist starts with "But our experience is also critical to what makes us human".

[_space.pony_]

I learn more from this channel than others- topics I wouldn’t necessarily be interested in, I’ll dive into because Eons covered it! Love your content

[GaryJohnWalker]

Great vid. And it showed how out of date my (limited) knowledge on genetics was. To think, just over 20 years ago with the first (almost!) complete humand genome sequencing it seemed like job all but done - a bit of mapping of genes to structure and the role of the odd control genes, variation, and that's human genetics wrapped up. Any more delving into genetic structure/function would be welcome!

[SiriProject]

I'm an IT guy so I guess we used to think that we would find what makes us by looking at tables in a database, when all the important stuff were actually the triggers at the back end.

[amandaewoldt]

Can you do an episode on epigenetics? Could that explain some of the variance we see despite our smaller number of genes?

I've been amazed about how little we know about human genetics and yet also how available genetic testing has come. I'm closely connected to the medically complex community and many many people have health issues that are likely genetic but science is not able to identify the reason.