500 Million Year Old was a "mistake" that lead to humanity

harleysportster
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500 Million Year Old was a "mistake" that lead to humanity

 So there is good news and bad news. Good news is cellular communication, bad news is that we are all just a "mistake". Guess my mother was right in a fit of anger as a kid when she said that I was an "unplanned pregnancy". Which is really not my fault that she did not believe in birth control (Catholic guilt and all). 

http://news.discovery.com/human/evolution/dna-mistake-evolution-120724.htm

 

THE GIST

- A genetic process that went wrong 500 million years ago led to the evolution of humans and other vertebrates.

- The event, which resulted in doublings of genes, also led to proteins responsible for many of today's diseases.

- Studying these proteins could help researchers learn more about human evolution and the inner workings of diseases.

Over 500 million years ago a spineless creature on the ocean floor experienced two successive doublings in the amount of its DNA, a "mistake" that eventually triggered the evolution of humans and many other animals, says a new study.

The good news is that these ancient DNA doublings boosted cellular communication systems, so that our body cells are now better at integrating information than even the smartest smartphones. The bad part is that communication breakdowns, traced back to the very same genome duplications of the Cambrian Period, can cause diabetes, cancer and neurological disorders

"Organisms that reproduce sexually usually have two copies of their entire genome, one inherited from each of the two parents," co-author Carol MacKintosh explained to Discovery News. "What happened over 500 million years ago is that this process 'went wrong' in an invertebrate animal, which somehow inherited twice the usual number of genes. In a later generation, the fault recurred, doubling the number of copies of each gene once again."

PHOTOS: Evolution Before Your Eyes

MacKintosh, a professor in the College of Life Sciences at the University of Dundee, said that such duplications also happened in plant evolution. As for the progeny of the newly formed animal, they remarkably survived and thrived.

"The duplications were not stable, however, and most of the resulting gene duplicates were lost quickly -- long before humans evolved," she continued. But some did survive, as MacKintosh and her team discovered.

Her research group studies a network of several hundred proteins that work inside human cells to coordinate their responses to growth factors and to insulin, a hormone. Key proteins involved in this process are called 14-3-3.

For this latest study, the scientists mapped, classified and conducted a biochemical analysis of the proteins. This found that they date back to the genome duplications, which occurred during the Cambrian.

WIDE ANGLE: Ready, Set, Evolve!

The inherited proteins appear to have evolved to make a "team" that can tune into more growth factor instructions than would be possible with a single protein.

"These systems inside human cells therefore behave like the signal multiplexing systems that enable our smartphones to pick up multiple messages," MacKintosh shared.

The teamwork may not always be a good thing, though. The researchers propose that if a critical function were performed by a single protein, as in amphioxus, then its loss or mutation would likely be lethal, resulting in no disease.

If multiple proteins are working as a team, however, and one or more becomes lost or mutated, the individual may survive, but could still wind up with a debilitating disorder. Such breakdowns could help to explain how diseases, such as diabetes and cancer, are so entrenched in humans.

HOWSTUFFWORKS: How Evolution Works

"In type 2 diabetes, muscle cells lose their ability to absorb sugars in response to insulin," MacKintosh said. "In contrast, greedy cancer cells don't await instructions, but scavenge nutrients and grow out of control."

Chris Marshall, a professor of cell biology at the Institute of Cancer Research at Royal Cancer Hospital, told Discovery News that he thinks the research "gives new insights into the evolution of signaling mechanisms that control cell behavior."

MacKintosh and her team are now focusing on the protein families whose upset causes melanoma and neurological disorders. Because of the likely connection to ancient genetic events, the research could shed light on human and other animal evolution while also helping to unravel diseases.

“It is proof of a base and low mind for one to wish to think with the masses or majority, merely because the majority is the majority. Truth does not change because it is, or is not, believed by a majority of the people.”
― Giordano Bruno


Vastet
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I wouldn't call it a mistake

I wouldn't call it a mistake per se. Gentically there are two different mechanisms that lead to evolving species. One is excessive copying of genes, and the other is deletion of genes. If either of these can be considered a mistake, then all of evolution is a mistake. It pre-supposes that reproduction has specific goals, and one of those goals is to make the offspring a perfect replica of the parent. I don't see how anyone could conclude that is true.

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of course it's not a


of course it's not a "mistake." how does nature make "mistakes"? it's like in my english conversation classes when we get on the topic of homosexuality, invariably a couple students will say it's "unnatural." i always respond that everything that exists is "natural."

i fucking despise teleological thinking, and it seems to me atheists are just as guilty of it as theists. NOTHING has a fucking "purpose."

"I have never felt comfortable around people who talk about their feelings for Jesus, or any other deity for that matter, because they are usually none too bright. . . . Or maybe 'stupid' is a better way of saying it; but I have never seen much point in getting heavy with either stupid people or Jesus freaks, just as long as they don't bother me. In a world as weird and cruel as this one we have made for ourselves, I figure anybody who can find peace and personal happiness without ripping off somebody else deserves to be left alone. They will not inherit the earth, but then neither will I. . . . And I have learned to live, as it were, with the idea that I will never find peace and happiness, either. But as long as I know there's a pretty good chance I can get my hands on either one of them every once in a while, I do the best I can between high spots."
--Hunter S. Thompson


harleysportster
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Perhaps the article

Perhaps the article could have picked a better term than mistake. Not that I really care about what term the person writing this thing up for some extra space in the paper might have used. Just found it a bit interesting of a read. But then again, I am not too terribly worried about the semantics of the thing one way or the other. 

 

“It is proof of a base and low mind for one to wish to think with the masses or majority, merely because the majority is the majority. Truth does not change because it is, or is not, believed by a majority of the people.”
― Giordano Bruno