Roughly 8 percent of your DNA isn’t really human. (How’s that for a morning wake-up call?) Instead, it’s the de-activated remnants of ancient retroviruses. All viruses hijack host cell machinery to replicate themselves, but retroviruses are a little more invasive than most. These viruses trick cells into turning viral RNA into DNA—the reverse of the normal DNA to RNA transcription process—and then snuggle that DNA right into the rest of the host’s genome. They mutate frequently and, sometimes, accidentally deactivate themselves—in which case the “dead” viral DNA just ends up hanging out in the human genome.
I’ve based the plot of my upcoming indie game around this concept, even keeping the name of the virus. You can probably guess what makes up the majority of the enemies.
hehehehe - wondered what your response would be :D
Back on topic, what we’re going to find is more and more of the “junk DNA” a really crappy term to describe traditional non-coding DNA contains a lot of ancient artifacts. If we had the means and the money I bet there could be a lot more associations made between (not just viral DNA, & RNA) but bacterial segments as well.
Only a matter of time… maybe this is what we’ll see in Phil S’s go to the future thread in 3,000 AD
Funny this thread got bumped. One of my current projects is looking at pseudogene expression. Man, these are complicated little buggers.
Sometimes you have DNA that makes RNA, and then it get swapped back into your genome in it’s fully spliced together form. Only problem is, there’s no signal sequence for the sequence to be turned back into RNA, so it just chills out and slowly mutates over time. This DNA isn’t under selection, so it mutates much more quickly than other regions that if they get mutated you don’t stay alive.
Other times, you just copy the gene wholesale in the unspliced state. This can lead to additional expression of the gene, but again since you’ve already got a copy of the gene, you don’t need to maintain that bonus copy and the gene starts to mutate. These are sometimes a bitch for me, as they can look 70-98% like the original gene, which can make sequencing those regions more confusing.
Other times, even though we say they aren’t “active” because they don’t create a full protien molecule like the original copy, the partial protein can do wacky things, like compete with the original copy of the protein to interact with other proteins. In some cases, this can increase or decrease the amount of the original protein, which can suppress or cause cancer. Fun!
