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Posted: Tue Apr 24, 2007 5:31 pm
by Charlie Hatchett
Transposons are not really "junk" DNA, but mutagens. Drastically change the environment somehow, and you'll need them
Built in variability. 8)

Freeking cool. :wink:

Posted: Wed Apr 25, 2007 1:47 am
by Digit
Trinkaus deserves a medal. For courage!

Posted: Mon Apr 30, 2007 11:58 am
by Beagle
http://www.washingtonpost.com/wp-dyn/co ... 01101.html
One geneticist, Bruce T. Lahn of the University of Chicago, has even proposed that Neanderthals may have provided genetic material that helped in human brain development. Lahn has been studying such genes, in particular a gene called microcephalin. A mutation of that gene can cause microcephaly, which leaves a child with a very small head and serious neurological problems.

Lahn's studies indicated that a new and more powerful version of the gene arose in modern humans about 40,000 years ago. In a paper last year, he concluded that the two microcephalin genes are so different that they must have diverged about 1 million years ago, around the time of the split between those that would become Neanderthals and the homo sapiens destined to become modern humans.

Lahn's explanation of the information: The newer and better version of the gene evolved in a separate species -- most likely Neanderthals -- and then entered the gene pool of modern humans through interbreeding around the time that modern humans reached Europe.
More views from Trinkaus et others on HNS. Posted in Archaeologica News.

Posted: Mon Apr 30, 2007 12:04 pm
by Charlie Hatchett
Cool stuff, Beag. 8)

Posted: Mon Apr 30, 2007 12:21 pm
by Beagle
Hi Charlie, I've got some catching up to do, since I've been playing hookie out in this beautiful weather.

I've come down with "spring fever" :wink:

Posted: Mon Apr 30, 2007 12:24 pm
by Digit
Interesting article, I think the world is coming round to my viewpoint.

Posted: Mon Apr 30, 2007 12:31 pm
by Minimalist
Lahn's studies indicated that a new and more powerful version of the gene arose in modern humans about 40,000 years ago. In a paper last year, he concluded that the two microcephalin genes are so different that they must have diverged about 1 million years ago, around the time of the split between those that would become Neanderthals and the homo sapiens destined to become modern humans.

So.....it would seem that the idea could be tested by comparing the frequency of the gene in European populations with African populations. No indication if they did so.

Posted: Mon Apr 30, 2007 12:46 pm
by Beagle
Exactly Min. That would seem to be the thing to do.

Posted: Mon Apr 30, 2007 1:07 pm
by Minimalist
I don't know...maybe its just me. I don't get why people come up with these ideas and then don't test them out.

You can still invite others to re-do the tests themselves. Experimentation is a big part of science. Just Do It.

D Allele frequency

Posted: Mon Apr 30, 2007 3:33 pm
by Cognito
So.....it would seem that the idea could be tested by comparing the frequency of the gene in European populations with African populations. No indication if they did so.
Actually, guys, I believe they did do that. Dig a little deeper and you'll find the variance in distribution. However, the results are not at all popular with some individuals due to the potential for racial interpretations, etc. :roll:

Posted: Mon Apr 30, 2007 3:57 pm
by Minimalist
I didn't get a whiff of that, Cogs, or I wouldn't have noted it. What I spotted was this:
Trinkaus, of Washington University in St. Louis, analyzed prehistoric fossil remains from various parts of Europe.
No indication there of any cross-referencing to a population which remained in Africa.

Although, I think you touch on a major facet of political correctness in modern society with your observation.

They are going to have to be a little less murky in their discussions.

Re: D Allele frequency

Posted: Mon Apr 30, 2007 4:01 pm
by Charlie Hatchett
Cognito wrote:
So.....it would seem that the idea could be tested by comparing the frequency of the gene in European populations with African populations. No indication if they did so.
Actually, guys, I believe they did do that. Dig a little deeper and you'll find the variance in distribution. However, the results are not at all popular with some individuals due to the potential for racial interpretations, etc. :roll:
I personally would be giddy to see a good hunk of haplogroup X2 and European Neanderthal mixed up together. I've got this hunch I'm chasing: Solutreans were a hybrid of HNs and Hss. It's like they came out of nowhere. :?
One geneticist, Bruce T. Lahn of the University of Chicago, has even proposed that Neanderthals may have provided genetic material that helped in human brain development.

Origin of D Allele

Posted: Mon Apr 30, 2007 4:41 pm
by Cognito
Here is the article that discusses the potential origin of the D Allele as being from Eurasia as opposed to sub-Saharan Africa:

http://www.hhmi.org/news/pdf/lahn20061006.pdf

It just ain't politically correct thinking! :shock:

Posted: Tue May 01, 2007 5:54 am
by Beagle
Nice article Cogs. Here is a discussion with John Kaufman, the science writer at the Washington Post on the earlier article I posted.

http://www.washingtonpost.com/wp-dyn/co ... 01501.html

From a link on that article.

Admixture

Posted: Tue May 01, 2007 6:50 pm
by Cognito
Interesting article, Beags. And I cannot ignore the shovel incisor comment that indicates admixture. Only three populations had/have shovel incisor teeth:

1. Homo erectus
2. East asians
3. Native americans

Someone was getting to know the native population quite well as they were migrating east to the Americas! I'll tell ya, that Homo erectus, you just can't keep a good man down! :D