Posted on 11/26/2007 4:13:41 PM PST by blam
Contact: Anne Rueter
arueter@umich.edu
734-764-2220
University of Michigan Health System
11-26-2007
Gene study supports single main migration across Bering Strait
Siberians and Native Americans share unique genetic variant
The U-M study, which analyzed genetic data from 29 Native American populations, suggests a Siberian origin is much more likely than a South Asian or Polynesian origin.
Did a relatively small number of people from Siberia who trekked across a Bering Strait land bridge some 12,000 years ago give rise to the native peoples of North and South America?
Or did the ancestors of today’s native peoples come from other parts of Asia or Polynesia, arriving multiple times at several places on the two continents, by sea as well as by land, in successive migrations that began as early as 30,000 years ago?
The questions – featured on magazine covers and TV specials – have agitated anthropologists, archaeologists and others for decades.
University of Michigan scientists, working with an international team of geneticists and anthropologists, have produced new genetic evidence that’s likely to hearten proponents of the land bridge theory. The study, published online in PLoS Genetics, is one of the most comprehensive analyses so far among efforts to use genetic data to shed light on the topic.
The researchers examined genetic variation at 678 key locations or markers in the DNA of present-day members of 29 Native American populations across North, Central and South America. They also analyzed data from two Siberian groups. The analysis shows:
o genetic diversity, as well as genetic similarity to the Siberian groups, decreases the farther a native population is from the Bering Strait – adding to existing archaeological and genetic evidence that the ancestors of native North and South Americans came by the northwest route.
o a unique genetic variant is widespread in Native Americans across both American continents – suggesting that the first humans in the Americas came in a single migration or multiple waves from a single source, not in waves of migrations from different sources. The variant, which is not part of a gene and has no biological function, has not been found in genetic studies of people elsewhere in the world except eastern Siberia.
The researchers say the variant likely occurred shortly prior to migration to the Americas, or immediately afterwards.
“We have reasonably clear genetic evidence that the most likely candidate for the source of Native American populations is somewhere in east Asia,” says Noah A. Rosenberg, Ph.D., assistant professor of human genetics and assistant research professor of bioinformatics at the Center for Computational Medicine and Biology at the U-M Medical School and assistant research professor at the U-M Life Sciences Institute.
“If there were a large number of migrations, and most of the source groups didn’t have the variant, then we would not see the widespread presence of the mutation in the Americas,” he says.
Rosenberg has previously studied the same set of 678 genetic markers used in the new study in 50 populations around the world, to learn which populations are genetically similar and what migration patterns might explain the similarities. For North and South America, the current research breaks new ground by looking at a large number of native populations using a large number of markers.
The pattern the research uncovered – that as the founding populations moved south from the Bering Strait, genetic diversity declined – is what one would expect when migration is relatively recent, says Mattias Jakobsson, Ph.D., co-first author of the paper and a post-doctoral fellow in human genetics at the U-M Medical School and the U-M Center for Computational Medicine and Biology. There has not been time yet for mutations that typically occur over longer periods to diversify the gene pool.
In addition, the study’s findings hint at supporting evidence for scholars who believe early inhabitants followed the coasts to spread south into South America, rather than moving in waves across the interior.
“Assuming a migration route along the coast provides a slightly better fit with the pattern we see in genetic diversity,” Rosenberg says.
The study also found that:
Populations in the Andes and Central America showed genetic similarities.
Populations from western South America showed more genetic variation than populations from eastern South America.
Among closely related populations, the ones more similar linguistically were also more similar genetically.
Hmmm, this is most interesting. You’re saying that the ojibwa are, by now, not “pure” genetic amerind DNA, 25% are european DNA ancestry(’X’). We do know that some of the amerinds came down the interior valleys of Canada as we see in the buffalo jumps/fossil evidence. They then were your ‘B’ types, yes?
And yet the A-C-D types worked their way down the coast all the way to south america. This may explain the unexpected finding of a 40,000 year old culture in chile. Of course that may be just a C14 carbon dating mistake, who knows? Then there’s the anomoly of the Kenniwick Man.
I’ve read/seen where europeans were actually in northern china, as seen in the fossil evidence. The dividing line between amerinds and polynesians was somewhere thru the middle of china. The original japanese culture, beyond the ainu, came from KOREA(the lesser of the 2 kingdoms then); this really makes the japanese “lose face” as they’ve always considered the koreans inferiors(my son just married a korean girl).
Then there were the samoans who colonized the hawaiian islands 800 years ago but over the centuries lost contact w/samoa and became isolated, until Captain Cook showed up(note the union jack on the Hawaiian State flag). There were about 500,000 of them then. European diseases wiped all the natives out, only 35,000 survived because of inter-breeding with the portugeuse(immunity). Then the Spanish Galleons from the Philipines to mexico sailed AROUND hawaii for 200+ years, north and south, using the prevailing currents, and never knew they were there....
Then there was Easter Island, another polynesian colonization, but over population wiped them almost completely out(malthusian doctrine)as only a few were left when the Dutch discovered it in 1879(right date?).
What’s the difference? WRITING. The 3 R’s were first invented in Iraq/thereabouts, but the hebrews really took to it; that gave them a leg up on historical knowledge passed down through the generations whereas all these other people passed away into dust. It’s only by these modern scientific methods(archeology, DNA, etc)that we even know they existed. Now you know why you went to school and learned readin/writin/rithmatic : you communicate with the future....
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True.
Ping.
It supports the notion that the survivors come from the single stock. The other groups either did not intermingle and died out or they and their progeny were wiped out in the constant warfare that apparently characterized America before Columbus.
I learn something new every time I read one of these articles. Thank you!!!
All of the principal Archaeological systems are of the nature of religious tenets. It is how the “soft” sciences are done. Those who grew up with a theory will fight a new different one with their last breath. It is as if a theory is disproved then an archaeologist’s life is suddenly of no account. His discoveries and fame become dust.
The Eskimos are late arrivals and may not all have walked.
Yup.
But, Dennis Sanford shows them coming across the Atlantic too.
Sounds like the prehistoric version of the Oklahoma landrush.
“Ready? Set....wait for it...GOOOOOO!
All very interesting, but how does it help as a guide to the future? As to being totally engrossed in the past, to me it’s akin to driving down the street in reverse, looking in your rear view mirror. Even our ancient INA-mother would be far more interested, yes fascinated, with what we her ASCENDENTS are doing, where we’re going with our intelligence, communication skills. So, it’s an interesting scientific DNA study but as our lord said : let the dead past bury its dead. Move on, there are bigger and better things coming in our future....
More likely the Jaredites.....
Well...I'm a catastrophist and I believe we'll all die in a asteroid impact, super-volcano eruption or a viral pandemic. So... (It's just a matter of when)
I guess you were there. How else can you know it all?
This article doesn’t mention the fact that some of the older fossilized remains, like the Kennewick man, do not match the “native American” lines. You would think that remains that were found in Washington state would be more likely to match those that came across a northern land bridge if it was the only path of migration.
Yes, the skeletons/skulls are so old we may never get DNA from them.
Spirit Cave Man is the oldest mummy ever found in the Americas and is older than Kennewick Man. The Indians won't allow DNA testing and even want to destroy it by burying it.
I think that the next 20 years will be interesting.
Well this can’t be right. It contradicts Joe Smith’s novel!
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