Biologists have just found jumping genes, and no, those aren't the protein sequences that build kangaroos. They're DNA segments that can hop around the genome copy-and-pasting themselves in wherever the feel like, and they're in your head. Which may help explain how humanity hosts such an incredible spectrum from "Stephen Hawking" to "Someone who tabulates the statistical values of Pokemon."
These LINE-1 elements (Long INterspersed Element 1) are known to play a major part in simple organisms like yeast, whose large numbers and simple structures allow a lot of experimentation. LINE-1 modifications to the genome are far larger than random mutations, and offer the chance of accelerated evolution through a lucky combination - or death from a bad one.
In humans they're known to be active in immune system cells, allowing our defences to rapidly reconfigure and face a wide variety of pathogens (which are varying their own DNA to evade detection). These changes don't happen in the heart or organs, because there are only so many ways to pump blood and any major changes would likely lead to death. Which makes it all the more interesting that in the brain the "LINE-1 modification" switch seems to be jammed fully on. Professor Gage and colleagues at the Salk Institute for Biological Studies found far more copies of these elements in the brain tissue than anywhere else - indicating that copy-and-pasting is active there.
Could this cause problems? Certainly. It seems that evolution has decided adaptability of the group is more important than the neuronal stability of the individual, and human history seems to bear that out. This extra layer of adaptability, on top of the incredibly interconnected array of over one hundred trillion neurons, makes the mind the most massively mutable system ever created - so much so it's able to analyze itself. Or even read about other people analyzing it, like you're doing now.
Posted by Luke McKinney
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