Posted on 02/22/2008 11:13:14 AM PST by blam
Ancient 'Out Of Africa' Migration Left Stamp On European Genetic Diversity
Scientists compared more than 10,000 sequenced genes from 15 African-Americans and 20 European-Americans. The results suggest that European populations have proportionately more harmful variations, though it is unclear what effects these variations actually may have on the overall health of Europeans. (Credit: iStockphoto)
ScienceDaily (Feb. 22, 2008) — Human migration from Africa to Europe more than 30,000 years ago appears to have left a mark on the genes of Europeans today.
A Cornell-led study, reported in the Feb. 21 issue of the journal Nature, compared more than 10,000 sequenced genes from 15 African-Americans and 20 European-Americans. The results suggest that European populations have proportionately more harmful variations, though it is unclear what effects these variations actually may have on the overall health of Europeans.
Computer simulations suggest that the first Europeans comprised small and less diverse populations. That would have allowed mildly harmful genetic variations within those populations to become more frequent over time, the researchers report.
"What we may be seeing is a 'population genetic echo' of the founding of Europe," said Carlos Bustamante, assistant professor of biological statistics and computational biology at Cornell and senior co-author with Andrew Clark, a professor of molecular biology and genetics.
"Since we tend to think of European populations as quite large, we did not expect to see a significant difference in the distribution of neutral and deleterious variation between the two populations," said Bustamante. "It was quite surprising, but when we cross-checked our results to data sets gathered by other groups, we found the same trend."
The researchers focused on single nucleotide polymorphisms (SNPs), where a single DNA base pair (the smallest structural unit) in a gene's sequence had been altered. Genetic variations were classified as to whether a SNP was found in one or both populations. Some of these genetic changes led to amino acid changes in the proteins that the genes express, while others had no effect.
Collaborators at Max Planck Institute in Tübingen, Germany, and Harvard Medical School analyzed the amino acid changes and used a computer algorithm to predict whether the changes alter a protein's structure or function, and classified the changes into three categories: benign, possibly damaging or probably damaging.
Using that information, the Cornell group found that the European sample, while showing overall less genetic variation, had proportionately more amino acid changes and proportionately more harmful amino acid single nucleotide polymorphisms than the African sample.
"It's difficult to tell what the precise impact that a higher proportion of deleterious single nucleotide polymorphisms in the population will have on the average person's health," said Kirk Lohmueller, a graduate student in both Bustamante's and Clark's labs and the paper's lead author. "More detailed studies that involve sequencing many individuals both with and without certain diseases would better enable us to get at this question."
Future research may also reveal similar signatures as other populations left Africa for other geographic destinations.
Other Cornell co-authors include Amit Indap, Adam Boyko and Ryan Hernandez as well as Rasmus Nielsen, a former Cornell faculty member now at the University of Copenhagen, and Melissa Hubisz, a former Cornell programmer now at the University of Chicago. Celera Diagnostics performed the gene sequences.
The study was funded by the National Institutes of Health and National Science Foundation.
Adapted from materials provided by Cornell University.
GGG Ping.
Good article.
How can they call them 'harmful variations' if they don't know what effect they have? Maybe they're beneficial variations, huh?
An increase in variations would also lead to more posotive variations and may explain europeans quicker development.
35 person study,
garbage science for political gain.
This is no different than those 10 brains examined to determine nature vs nurture.
this makes me think of the concept that all the weak ones die out.
The immediate flaw in this study is that there is no qualitative to the genetic study just number of variations. (extremely suspect)
How do we know that the elimination of those variations was not in fact a positive to survival.
Kind of like a format war. The most universal format survives the longest.
I wonder how this jibes with the people from the basque region of spain. They are supposed to be the most genetically unique people.
btt
No they're not...their yDNA is overwhemingly R1b as is 68% of all Europeans and as high as 90% among the Irish.
You must be thinking about their unique language.
Map #2
The three groups of humans had taken refuge for so long that their DNA had naturally picked up mutations, and consequently can be defined into different haplogroups. As they spread from these refuges, Haplogroups R1b, I and R1a propagated across Europe.
- Haplogroup R1b is common on the western Atlantic coast as far as Scotland.
- Haplogroup I is common across central Europe and up into Scandinavia.
- Haplogroup R1a is common in eastern Europe and has also spread across into central Asia and as far as India and Pakistan.
These three major haplogroups account for approx 80% of Europe's present-day population.
Around 8,000 years ago (Map 3), the Neolithic peoples of the Middle East that had developed the new technology of agriculture began moving into Europe. There were several haplogroups involved, mainly E3b, F, J2 and G2.
Map #3
These Neolithic haplogroups came in several waves over time and are found predominantly along the Mediterranean coast. Around 20% of the present-day population are from these Neolithic haplogroups. What is interesting to note is that the agricultural technology spread much further than the people who first 'invented' it.
A little later, around 4,500 years ago, Haplogroup N3 began moving across from west of the Ural mountains. Haplogroup N3 follows closely the spread of the Finno-Ugric languages.
one topic later...
White Genetically Weaker Than Blacks, Study Finds
Fox News | Friday, February 22, 2008
Posted on 02/22/2008 2:13:54 PM EST by Sopater
http://www.freerepublic.com/focus/news/1974645/posts
The Neandertal EnigmaFrayer's own reading of the record reveals a number of overlooked traits that clearly and specifically link the Neandertals to the Cro-Magnons. One such trait is the shape of the opening of the nerve canal in the lower jaw, a spot where dentists often give a pain-blocking injection. In many Neandertal, the upper portion of the opening is covered by a broad bony ridge, a curious feature also carried by a significant number of Cro-Magnons. But none of the alleged 'ancestors of us all' fossils from Africa have it, and it is extremely rare in modern people outside Europe." [pp 126-127]
by James Shreeve
|
|
|||
Gods |
Thanks Blam. |
||
|
· Mirabilis · Texas AM Anthropology News · Yahoo Anthro & Archaeo · · History or Science & Nature Podcasts · Excerpt, or Link only? · cgk's list of ping lists · |
|||
Only problem for this line of research is the "African-American" genes they are comparing have been so interbreed with European genes over the centuries that they represent a hybrid, not a pure bred strain.
“A Cornell-led study, reported in the Feb. 21 issue of the journal Nature, compared more than 10,000 sequenced genes from 15 African-Americans and 20 European-Americans. The results suggest that European populations have proportionately more harmful variations, though it is unclear what effects these variations actually may have on the overall health of Europeans. “
Politically correct biological tripe.
Not satisfied with attacking European civilization - which is the parent of American society and culture, they are now attacking our biology.
Interesting article though - after you slice through the tripe.
The facts are there, but INTERPRETATION of the facts are warped by the increasingly self-destructive nature of western caucasions.
I’m white and proud of it, and proud of my European heritage.
I don’t need to apologize for anything and I’m sick and tired of masochistic myopic white academics attacking MY heritage.
Calm down Blam is a good man. I don’t believe in the out of Africa theory myself for reasons other than genetics, mainly because it is a tautology, and I hate those things.
Maybe.
I was thinking something similar when I saw the picture of the 'African-American' female in the picture above. She seems to have more European facial features than African.
I'm in agreement with that sentiment.
I wasn’t attacking the poster, I was attacking the article’s premise.
Disclaimer: Opinions posted on Free Republic are those of the individual posters and do not necessarily represent the opinion of Free Republic or its management. All materials posted herein are protected by copyright law and the exemption for fair use of copyrighted works.