Posted on 11/15/2005 8:25:44 AM PST by balrog666
'Perception' gene tracked humanity's evolution, scientists say
A gene thought to influence perception and susceptibility to drug dependence is expressed more readily in human beings than in other primates, and this difference coincides with the evolution of our species, say scientists at Indiana University Bloomington and three other academic institutions. Their report appears in the December issue of Public Library of Science Biology.
The gene encodes prodynorphin, an opium-like protein implicated in the anticipation and experience of pain, social attachment and bonding, as well as learning and memory.
"Humans have the ability to turn on this gene more easily and more intensely than other primates," said IU Bloomington computational biologist Matthew Hahn, who did the brunt of the population genetics work for the paper. "Given its function, we believe regulation of this gene was likely important in the evolution of modern humans' mental capacity."
Prodynorphin is a precursor molecule of the neurotransmitters alpha-endorphin, dynorphin A, and dynorphin B, collectively called opioids because their action is similar to stimulatory effects caused by the drug opium.
The notion that humans are more perceptive than other primates would hardly be news. But the list of genes known to have tracked or guided humanity's separation from the other apes is a short one. Genes controlling the development of the brain almost always turn out to be identical or nearly so in chimpanzees and human beings. And as it turns out, the protein prodynorphin is identical in humans and chimps.
It's the prodynorphin gene's promoter sequence -- upstream DNA that controls how much of the protein is expressed -- where the big differences are. "Only about 1 to 1.5 percent of our DNA differs from chimpanzees," Hahn said. "We found that in a stretch of DNA about 68 base pairs in length upstream of prodynorphin, 10 percent of the sequence was different between us and chimps."
Hahn said this "evolutionary burst" is responsible for differences in gene expression rates. When induced, the human prodynorphin gene was 20 percent more active than the chimpanzee prodynorphin gene. Past research has also observed variation in expression levels within humans.
This report supports a growing consensus among evolutionary anthropologists that hominid divergence from the other great apes was fueled not by the origin of new genes, but by the quickening (or slowing) of the expression of existing genes.
Hahn and his colleagues at Duke University, University College London and Medical University of Vienna first became interested in primate prodynorphin after noticing an unusual amount of variation in the human version's promoter. The scientists decided to examine the prodynorphin gene in human beings around the world and in non-human primates to see whether such variation was commonplace and whether that variation affected gene expression.
The group found a surprisingly large amount of genetic variation among humans within the prodynorphin gene's promoter. They examined prodynorphin genes from Chinese, Papua New Guineans, (Asian) Indians, Ethiopians, Cameroonians, Austrians and Italians.
The group also sequenced and cloned prodynorphin genes from chimpanzees, gorillas, orangutans, rhesus macaques, pigtail macaques and guinea baboons. The researchers found that high genetic variation in the prodynorphin promoter was unique to humans. Other primates' promoters were far more homogeneous.
Exactly how prodynorphin influences human perception is unknown. Evidence for its various effects comes entirely from clinical studies of people who have mutations in the gene. Past clinical studies have also indicated a positive correlation between lower prodynorphin levels in the brain and susceptibility to cocaine dependence.
Matthew Rockman, David Goldstein and Gregory Wray (Duke University); Nicole Soranzo (University College London); and Fritz Zimprich (Medical University of Vienna) also contributed to the research. It was funded by grants from the National Science Foundation, NASA, the Royal Society, and the Leverhulme Trust (U.K.).
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More like the vermiform appendix. Just hanging out there and likely to cause problems.
I took FORTRAN 20 years ago in college. Promptly forgot it.
Puns, like Java, come only in descending grades. They start out bad and get worse.
However, if you rhyme your puns, you will certainly be accused of going from bad to verse.
However, if you rhyme your puns, you will certainly be accused of going from bad to verse.
Note that I refrained from using the obvious rhyme.
You didn't bother to read down to post #51 before replying, I see...
One example of many: Why would the "DESIGNER" of "ALL CREATION" give both us and the other primates the same *broken* copy of the gene that in most other animals performs Vitamin-C synthesis? And why would he design our broken copy of that gene to be slightly variant from the Chimp broken copy, more variant from the Gorilla broken copy, and so on, in a way that exactly matches the results of evolutionary divergence from successively older common ancestral branches?
I'm a SQL man, myself.
Bring back FORTRAN! (Then I can come back!)
Maybe this gene isn't broken at all like you claim.
I think it is hilarious that otherwise intelligent people continue to argue that they are in fact, monkeys.
God does have a sense of humor....
Apes, not monkeys.
Many cultures used A. muscaria. Not sure I would have wanted to be the one experimenting, especially when it came to A. palloides, but given the number of cultures worldwide who used the mushrooms, somebody did experiment.
It is also prevalent in the eastern Mediterranean (see John M. Allegro's book for details)--that's why I posted the photograph.
Nutjobs quote a 2,000 year old book, and claim that women were created from a man's rib.
"Eat my body, drink my blood" (Catholic song--I was indoctrinated)
and any programmer could tell at a glance whether a particular program was actually written by a human, or "grown/evolved" via genetic algorithmsOr rather, any programmer could tell if it was written by a normal human, or one of the following:
Maybe you're grasping at straws.
It's provably broken. Its miscoding results in failed Vitamin-C synthesis in primates. We provably are unable to make Vitamin-C from simpler chemicals in the food we eat, unlike almost all other animals. As a result, we are subject to nutritional diseases if we fail to get enough Vitamin-C directly in the foods we eat -- this is not a problem for almost all other non-primate animals, because their Vitamin-C-making genese are *not* broken in the way that ours are. We *do* have that gene (as well as the other genes which are involved in the multi-step process of Vitamin-C synthesis), but a copy error millions of years ago in the ancestral lineage of proto-primates screwed it up, and the entire primate lineage since then has inherited it the genetic error, resulting in the complete failure (and uselessness) of our otherwise intact Vitamin-C synthesis mechanism.
So again I ask: What kind of "DESIGNER" would insert broken genes into us *and* into the other primates, *and* do it in a way that is (in precise character, degree, and detail) exactly as predicted from an origin via evolutionary common descent?
Once you've answered that (if you ever manage to -- good luck!) we can move onto the subject of why man and other primates share endogenous retroviruses in a way impossible to explain via "design", and 100% expected via evolutionary common descent. And after *that*, I've got another several thousand thorny questions for you about how human DNA screams "common descent" instead of "common design".
I think it is hilarious that otherwise intelligent people continue to argue that they are in fact, monkeys.
*I* think it's hilarious that allegedly intelligent people are so ignorant of the vast and overwhelming evidence, along multiple independently cross-confirming lines, that we are indeed directly related to the other primates. I also think it's hilarious that these know-nothings feel compelled to ridicule the people who *are* familiar with the evidence, based on nothing more than their own emotional reaction to the concept of having distant simian relatives, and their own unawareness of their lack of an education on this matter.
Oh, and by the way: You Are an Ape. If you disagree, feel free to find any traits which are diagnostic of apes (i.e., which all apes characteristically have that non-ape animals do not) which humans do not *also* have as well.
God does have a sense of humor....
Apparently so, since He made so many people who are belligerently arrogant about their state of ignorance.
"...He made so many people who are belligerently arrogant about their state of ignorance."
At least I agree with your last sentence...
Run along, the grownups are having a conversation.
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