DNA News Page 5  -  last update 5/1/2013

-- Ancient Europeans mysteriously vanished 4,500 BC - 4/23/13
-- Ancient DNA Reveals Europe's Dynamic Genetic History - 4/23/13
-- DNA analysed from early European - 1/01/10
-- Europeans as a people are younger than we thought - 4/23/13
-- Analysis of hair DNA reveals ancient human's face - 2/10/10
-- Migrants from the Near East 'brought farming to Europe - 11/10/10

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 Modern Europe's Genetic History Starts in Stone Age

Scientists create the first detailed genetic history of modern Europe..

Europeans as a people are younger than we thought

 April 23, 2013     Ker Than     for National Geographic News

DNA recovered from ancient skeletons reveals that the genetic makeup of modern Europe was established around 4,500 B.C. in the mid-Neolithic—or 6,500 years ago—and not by the first farmers who arrived in the area around 7,500 years ago or by earlier hunter-gatherer groups. (Read about Europe's oldest known town.)

"The genetics show that something around that point caused the genetic signatures of previous populations to disappear," said Alan Cooper, director of the Australian Centre for Ancient DNA at the University of Adelaide, where the research was performed.

"However, we don't know what happened or why, and [the mid-Neolithic] has not been previously identified as [a time] of major change," he said.

Furthermore, the origins of the mid-Neolithic populations that did form the basis of modern Europe are also unknown.

"This population moves in around 4,000 to 5,000 [B.C.], but where it came from remains a mystery, as we can't see anything like it in the areas surrounding Europe," Cooper said.

The surprising findings are part of a new study, published in this week's issue of the journal Nature Communications, that provides the first detailed genetic history of modern Europe.

The study shows that "relatively recent migrations seem to have had a significant genetic impact on the population of Central Europe," said study co-author Spencer Wells, who leads National Geographic's Genographic Project. (Read about Europe's "Wild Men" in National Geographic magazine.)

Genetic Signature

In the study, Cooper and his colleagues extracted mitochondrial DNA—which children inherit only from their mothers—from the teeth and bones of 39 skeletons found in central Germany. The skeletons ranged in age from about 7,500 to 2,500 years old.

The team focused on a group of closely related mitochondrial lineages—mutations in mitochondrial DNA that are similar to one another—known as haplogroup H, which is carried by up to 45 percent of modern Europeans.

Cooper and his colleagues focused on haplogroup H because previous studies have indicated the mutations might have been present in Europeans' genetic makeup for several thousand years.

It's unclear how this haplogroup became dominant in Europe. Some scientists have proposed that it spread across the continent following a population boom after the end of the last ice age about 12,000 years ago.

But the new data paint a different picture of the genetic foundation of modern Europe: Rather than a single or a few migration events, Europe was occupied several times, in waves, by different groups, from different directions and at different times.

The first modern humans to reach Europe arrived from Africa 35,000 to 40,000 years ago. By about 30,000 years ago, they were widespread throughout the area while their close cousins, the Neanderthals, disappeared. Hardly any of these early hunter-gatherers carried the H haplogroup in their DNA.

About 7,500 years ago during the early Neolithic period, another wave of humans expanded into Europe, this time from the Middle East. They carried in their genes a variant of the H haplogroup, and in their minds knowledge of how to grow and raise crops. (Related: "Egypt's Earliest Farming Village Found.")

Archeologists call these first Central European farmers the linear pottery culture (LBK)—so named because their pottery often had linear decorations.

The genetic evidence shows that the appearance of the LBK farmers and their unique H haplogroups coincided with a dramatic reduction of the U haplogroup—the dominant haplogroup among the hunter-gatherers living in Europe at that time.

Farmers Move In

The findings settle a longstanding debate among archaeologists, said Wells, who is also a National Geographic explorer-in-residence.

Archaeology alone can't determine whether cultural movements—such as a new style of pottery or, in this case, farming—were accompanied by the movements of people, Wells said in an email.

"In this study we show that changes in the European archaeological record are accompanied by genetic changes, suggesting that cultural shifts were accompanied by the migration of people and their DNA."

The LBK group and its descendants were very successful and spread quickly across Europe. "They became the first pan-European culture, if you like," Cooper said.

Given their success, it would be natural to assume that members of the LBK culture were significant genetic ancestors of many modern Europeans.

But the team's genetic analysis revealed a surprise: About 6,500 years ago in the mid-Neolithic, the LBK culture was itself displaced. Their haplogroup H types suddenly became very rare, and they were subsequently replaced by populations bearing a different set of haplogroup H variations.

Mysterious Turnover

The details of this "genetic turnover" event are murky. Scientists don't know what prompted it, or even where the new colonizers came from.

"The extent or nature of this genetic turnover are not clear, and we don't know how widespread it is," Cooper said.

If this turnover were widespread, it could have been prompted by climate change or disease, he said.

"All we know is that the descendants of the LBK farmers disappeared from Central Europe about 4,500 [B.C.], clearing the way for the rise of populations from elsewhere, with their own unique H signatures."

Peter Bogucki, an archeologist at Princeton University who has studied early farming societies in Europe, called the finding "really interesting" and noted the timing of the genetic turnover is curious.

"At the end of the fifth millennium—[about] 4,000 B.C.—there are a lot of changes in the archeological record," said Bogucki, who was not involved in the study.

For example, the long houses that LBK farmers and their descendants favored became less common. Also, the settlement patterns of people living in Central Europe began changing, as did their stone tools.

"There are major transformations during this time that haven't really been all that well explained in interior Central Europe," Bogucki said.

"It looks like the whole system of agricultural settlement that got established with the LBK ran its course through the fifth millennium and something caused people to change."

Of Unknown Origins

Bogucki agrees that climate change might have been a trigger for the change in Europe's genetic makeup, but he thinks it was only a factor and not the sole cause.

One thing that is clear from the genetic data is that nearly half of modern Europeans can trace their origins back to this mysterious group.

"About [4,500 B.C.], you start seeing a diversity and composition of genetic signatures that are beginning to look like modern [Central] Europe," Cooper said. "This composition is then modified by subsequent cultures moving in, but it's the first point at which you see something like the modern European genetic makeup in place."

Whatever prompted the replacement of genetic signatures from the first pan-European culture, Cooper is clearly intrigued. "Something major happened," he said in a statement, "and the hunt is now on to find out what that was."

Correction: The original version of this article stated that the genetic makeup of modern Europeans emerged 4,500 years ago. The text has been updated to reflect the correct timing as 4,500 B.C., or 6,500 years ago.

 Migrants from the Near East 'brought farming to Europe'

10 November 2010     By Katia Moskvitch     Science reporter, BBC News

The first farmers are believed to have brought domesticated cattle with them to Europe

Farming in Europe did not just spread by word-of-mouth, but was introduced by migrants from the ancient Near East, a study suggests.

Scientists analysed DNA from the 8,000 year-old remains of early farmers found at an ancient graveyard in Germany.

They compared the genetic signatures to those of modern populations and found similarities with the DNA of people living in today's Turkey and Iraq.

The study appears in the journal PLoS Biology.

Wolfgang Haak of the University of Adelaide in Australia led the team of international researchers from Germany, Russia and Australia.

Up until now, many scientists believed that the concept of farming was brought to Europe merely by the transfer of ideas. They thought that European hunter-gatherers living in close proximity to ancient farmers in the Near East were spreading the information about more settled ways and agriculture further north.

But the recent study challenges that hypothesis.

"We have shown that the first farmers in Europe had a much greater genetic input from the Near East and Anatolia, than from populations of Stone Age hunter-gatherers who already existed in the area," said Dr Haak.

A co-author, Professor Alan Cooper, also of the University of Adelaide, agreed.

"This helps to overturn current thinking, which accepts that the first European farming populations were constructed largely from existing populations of hunter-gatherers, who had either rapidly learned to farm or interbred with the invaders," he said.

Common ancestors

The scientists used the most modern techniques to extract the mitochondrial DNA - genetic code that is passed down via the maternal line - from the 8,000-year-old bones of 22 people buried at a graveyard at the town of Derenburg in Saxony-Anhalt in central Germany.

Past studies had already confirmed that the remains belonged to ancient European farmers from the Early Neolithic "Linear Pottery Culture".

An artist's impression of what an early Neolithic settlement might have looked like, some 8,000 years ago
The researchers then compared defining DNA segments known as haplotypes with those of people living across Eurasia today.

The existence of the same haplotypes in people from different regions shows that they share a common ancestor.

And that was exactly what Dr Haak's team found.

Richard Villems from the University of Tartu and Estonian Biocentre in Estonia, a co-author of the study, called the results exciting, but said that further studies might yield even more important results.

"The ancient DNA is much better preserved in cold Europe than in warmer places," he told BBC News.

"But if it were possible, and hopefully it will be possible in the future, to match it with some 8,000-10,000 year-old samples from the Near East, then it would really be perfect."

The analysis also revealed that the hunter-gatherer population living in Europe did not die out as a result of the "invasion" of the migrants from the Near East.

Instead, the two groups mingled together, which resulted in "mixed" ancestry, signs of which the team discovered at the graveyard.

One of the houses in the Neolithic settlement at Skara Brae, in Scotland's Orkney islands
Spencer Wells, director of the Genographic Project, a large-scale genetic survey of human migration, explained to BBC News that the farmers moved via a route from the Near East and Anatolia, where farming evolved around 11,000 years ago, to south-eastern and then Central Europe.

They then continued moving further north, possibly because of climate change, mixing with the indigenous population along the way.

These conclusions, he added, are an important argument in the nearly half-century long debate about the origins of farming in Europe.

"It seems to point to a natural migration of human beings out of the Near East moving into Europe, spreading the farming culture," said Dr Wells.


 Analysis of hair DNA reveals ancient human's face
10 February 2010 By Doreen Walton Science reporter, BBC News

Tufts of hair from "Inuk" were found preserved in Greenland's permafrost
DNA analysis of human hair preserved in Greenland's permafrost has given clues as to what the owner looked like.

A study, published in the journal Nature, says the individual's genome is the oldest to have been sequenced from a modern human.

The researchers say the man, who lived 4,000 years ago, had brown eyes and thick dark hair, although he would have been prone to baldness.

They say the genome also shows that his ancestors migrated from Siberia.

The man has been named Inuk, which means "human" in the Greenlandic language.

"We wanted to acknowledge that he was from Greenland, even though he is not a direct ancestor of modern Greenlanders," said Professor Eske Willerslev from the University of Copenhagen, who took part in the study.

They must have crossed either by boat or in the winter time over the ice. No one knows

Professor Eske Willerslev
The researchers say an analysis of the genome shows that Inuk was from the Saqqaq culture.

The team now has genetic evidence that Inuk's metabolism and body mass meant he was adapted to living in a cold climate.

The Saqqaq hunted seals and seabirds and relied on the sea for most of their food. Archaeological remains show they lived in tiny tents in winter.

"It's a very hostile environment and I was really surprised that people could live up there," explained Professor Willerslev.

Inuk had shovel-shaped front teeth, according to the research team. He also had dry earwax, which would have made him more vulnerable to ear infections.

He is thought to have died young because, although his genes show susceptibility to baldness, tufts of thick hair were found.

Siberian connection

The analysis took a year and the genome sequence suggested that the Saqqaq's closest living relatives were native populations in north-eastern Siberia, such as the Chuckchis and the Koryaks. The scientists say the Saqqaqs were probably not ancestors of contemporary Inuit or Native American populations.

This suggests, the researchers say, that the Saqqaqs migrated from Siberia to the New World approximately 5,500 years ago. This would have been independent of the movement that gave rise to modern Native Americans and Inuit.

Professor Willerslev explained that it was not known how the people made the crossing from Siberia to Greenland and Alaska.

"There was no land bridge between Siberia and Alaska at that time, so they must have crossed either by boat or in the winter time over the ice. No one knows," he said.

What happened to the Saqqaq people and why they died out also remains a mystery. "Was it climatic change, was it competition from other cultures coming in? We have no idea," said Professor Willerslev.


 DNA analysed from early European
By Paul Rincon
Science reporter, BBC News

The DNA comes from the skeleton of a male in his twenties
Scientists have analysed DNA extracted from the remains of a 30,000-year-old European hunter-gatherer.

Studying the DNA of long-dead humans can open up a window into the evolution of our species (Homo sapiens).

But previous studies of this kind have been hampered by scientists' inability to distinguish between the ancient human DNA and modern contamination.

In Current Biology journal, a German-Russian team details how it was possible to overcome this hurdle.

Svante Paabo, from the Max Planck Institute for Evolutionary Anthropology in Leipzig, Germany, and colleagues used the latest DNA sequencing techniques to study genetic information from human remains unearthed in 1954 at Kostenki, Russia.

Excavations at Kostenki, on the banks of the river Don in southern Russia, have yielded large concentrations of archaeological finds from the Palaeolithic (roughly 40,000 years ago to 10,000 years ago). Some of the finds date back as far as 45,000 years.

The ironic thing is that our group has been one of those that raised this issue

Professor Svante Paabo, Max Planck Institue
The DNA analysed in this study comes from a male aged 20-25 who was deliberately buried in an oval pit some 30,000 years ago.

Known as the Markina Gora skeleton, it was found lying in a crouched position with fists reaching upwards and a face orientated down towards the dirt. The bones were covered in a pigment called red ochre, thought to have been used in prehistoric funeral rites.

The type of DNA extracted and analysed is that stored in mitochondria - the "powerhouses" of cells. This mitochondrial DNA (mtDNA) is passed down from a mother to her offspring, providing a unique record of maternal inheritance.

Using technology pioneered in the study of DNA from Neanderthal bones, they were able to distinguish between ancient genetic material from the Kostenki male and contamination from modern people who handled the bones, or whose DNA reached the remains by some other means.

The ancient skeleton was unearthed in 1954 at Kostenki in Russia (Courtesy of Vladimir Gorodnyanskiy)
The new approach, developed by Professor Paabo and his colleagues, exploits three features which tend to distinguish ancient DNA from modern contamination. One of these is size; fragments of ancient DNA are often shorter than those from modern sources.

Previous ancient DNA studies used the widespread polymerase chain reaction (PCR) technology. PCR amplifies a few pieces of genetic material, generating thousands to millions of copies of a sequence. But the researchers found many fragments of ancient DNA were too small to be amplified by PCR.

A second characteristic of ancient DNA was its tendency to show particular changes, or mutations, in the genetic sequence at the ends of DNA molecules.

A third feature was a characteristic breakage of molecules at particular positions in the DNA strand.

Trust issues

The apparent ease with which modern DNA can infiltrate ancient remains has led many researchers to doubt even those studies employing the most rigorous methods to weed out contamination by modern genetic material.

"The ironic thing is that our group has been one of those that raised this issue," Professor Paabo told BBC News.

"To take animal studies on cave bears, for example, if we use PCR primers specific for human DNA on cave bear bones, we can retrieve modern human DNA on almost every one. That has made me think: 'how can I trust anything on this'."

Large concentrations of Palaeolithic finds have come from Kostenki
Using the new techniques, the researchers were able to sequence the entire mitochondrial genome of the Markina Gora individual.

Future studies like the one in Current Biology could help shed light on whether the humans living in Europe 30,000 years ago are the direct ancestors of modern populations or whether they were replaced by immigrants who introduced farming to the continent several thousand years ago.

The modern gene pool contains a wide variety of mtDNA lineages. Studying these maternal lineages provides scientists with clues to the origins and histories of human populations.

Scientists look for known genetic signatures in order to classify an individual's mtDNA into different types, or "haplogroups". These haplogroups represent major branches on the family tree of Homo sapiens.

Early arrival

The researchers were able to assign the Kostenki individual to haplogroup "U2", which is relatively uncommon among modern populations.

U2 appears to be scattered at low frequencies in populations from South and Western Asia, Europe and North Africa.

Despite its rarity, the very presence of this haplogroup in today's Europeans suggests some continuity between Palaeolithic hunters and the continent's present-day inhabitants, argue the authors of the latest study.

Distinguishing ancient DNA from modern has been difficult until now
U2, along with closely related haplogroups such as U5, are among those which could plausibly have arrived in Europe during the Palaeolithic.

Geneticists use well-established techniques to "date" particular genetic events, such as when a haplogroup first diversified. The "U" branch (comprising haplogroups U1, U2, U3 and so on) appears to be more ancient than many other genetic lineages found in Europe.

A recent study found a very high percentage of U types in the skeletal remains of ancient hunter-gatherers from Central Europe compared with later farming immigrants and modern people from the region.

Meanwhile, an analysis last year of mtDNA from 28,000-year-old remains unearthed at Paglicci Cave in Italy showed this individual belonged to haplogroup "H" - the most common type found in modern Europeans.


 Ancient Europeans mysteriously vanished 4,500 BC

Published April 23, 2013 LiveScience

DNA taken from ancient European skeletons reveals that the genetic makeup of Europe mysteriously transformed about 4,500 years ago, new research suggests. Here, a skeleton, not used in the study, but from the same time period, that was excavated from a grave in Sweden. (öran Burenhult)

The genetic lineage of Europe mysteriously transformed about 4,500 BC, new research suggests.

The findings, detailed today (April 23, 2013) in the journal Nature Communications, were drawn from several skeletons unearthed in central Europe that were up to 7,500 years old.

"What is intriguing is that the genetic markers of this first pan-European culture, which was clearly very successful, were then suddenly replaced around 4,500 BC, and we don't know why," said study co-author Alan Cooper, of the University of Adelaide Australian Center for Ancient DNA, in a statement. "Something major happened, and the hunt is now on to find out what that was."

The new study also confirms that people sweeping out from Turkey colonized Europe, likely as a part of the agricultural revolution, reaching Germany about 7,500 years ago. 

For decades, researchers have wondered whether people, or just ideas, spread from the Middle East during the agricultural revolution that occurred after the Mesolithic period.  To find out, Cooper and his colleagues analyzed mitochondrial DNA, which resides in the cells' energy-making structures and is passed on through the maternal line, from 37 skeletal remains from Germany and two from Italy; the skeletons belonged to humans who lived in several different cultures that flourished between 7,500 and 2,500 years ago. The team looked a DNA specifically from a certain genetic group, called haplogroup h, which is found widely throughout Europe but is less common in East and Central Asia.

The researchers found that the earliest farmers in Germany were closely related to Near Eastern and Anatolian people, suggesting that the agricultural revolution did indeed bring migrations of people into Europe who replaced early hunter-gatherers.

But that initial influx isn't a major part of Europe's genetic heritage today.  Instead, about 5,000 to 4,000 BC, the genetic profile changes radically, suggesting that some mysterious event led to a huge turnover in the population that made up Europe.

The Bell Beaker culture, which emerged from the Iberian Peninsula around 2800 B.C., may have played a role in this genetic turnover. The culture, which may have been responsible for erecting some of the megaliths at Stonehenge, is named for its distinctive bell-shaped ceramics and its rich grave goods. The culture also played a role in the expansion of Celtic languages along the coast.

"We have established that the genetic foundations for modern Europe were only established in the Mid-Neolithic, after this major genetic transition around 4,000 BC," study co-author Wolfgang Haak, also of the Australian Center for Ancient DNA, said in a statement. "This genetic diversity was then modified further by a series of incoming and expanding cultures from Iberia and Eastern Europe through the Late Neolithic."

Read more: http://www.foxnews.com/science/2013/04/23/ancient-europeans-mysteriously-vanished-4500-years-ago-660620043/#ixzz2T8KDJu13

 Ancient DNA Reveals Europe's Dynamic Genetic History

Ancient DNA recovered from a series of skeletons in central Germany up to 7,500 years old has been used to reconstruct the first detailed genetic history of modern Europe. Apr. 23, 2013 — Ancient DNA recovered from a series of skeletons in central Germany up to 7,500 years old has been used to reconstruct the first detailed genetic history of modern Europe.

The study, published today in Nature Communications, reveals a dramatic series of events including major migrations from both Western Europe and Eurasia, and signs of an unexplained genetic turnover about 4,000 to 5,000 BC.

The research was performed at the University of Adelaide's Australian Centre for Ancient DNA (ACAD). Researchers used DNA extracted from bone and teeth samples from prehistoric human skeletons to sequence a group of maternal genetic lineages that are now carried by up to 45% of Europeans.

The international team also included the University of Mainz in Germany and the National Geographic Society's Genographic Project.

"This is the first high-resolution genetic record of these lineages through time, and it is fascinating that we can directly observe both human DNA evolving in 'real-time', and the dramatic population changes that have taken place in Europe," says joint lead author Dr Wolfgang Haak of ACAD.

"We can follow over 4,000 years of prehistory, from the earliest farmers through the early Bronze Age to modern times."

"The record of this maternally inherited genetic group, called Haplogroup H, shows that the first farmers in Central Europe resulted from a wholesale cultural and genetic input via migration, beginning in Turkey and the Near East where farming originated and arriving in Germany around 7,500 years ago," says joint lead author Dr Paul Brotherton, formerly at ACAD and now at the University of Huddersfield, UK.

ACAD Director Professor Alan Cooper says: "What is intriguing is that the genetic markers of this first pan-European culture, which was clearly very successful, were then suddenly replaced around 4,500 BC, and we don't know why. Something major happened, and the hunt is now on to find out what that was."

The team developed new advances in molecular biology to sequence entire mitochondrial genomes from the ancient skeletons. This is the first ancient population study using a large number of mitochondrial genomes.

"We have established that the genetic foundations for modern Europe were only established in the Mid-Neolithic, after this major genetic transition around 4,000 years ago," says Dr Haak. "This genetic diversity was then modified further by a series of incoming and expanding cultures from Iberia and Eastern Europe through the Late Neolithic."

"The expansion of the Bell Beaker culture (named after their pots) appears to have been a key event, emerging in Iberia around 2800 BC and arriving in Germany several centuries later," says Dr Brotherton. "This is a very interesting group as they have been linked to the expansion of Celtic languages along the Atlantic coast and into central Europe."

"These well-dated ancient genetic sequences provide a unique opportunity to investigate the demographic history of Europe," says Professor Cooper.

"We can not only estimate population sizes but also accurately determine the evolutionary rate of the sequences, providing a far more accurate timescale of significant events in recent human evolution."

The team has been working closely on the genetic prehistory of Europeans for the past 7-8 years.

Professor Kurt Alt (University of Mainz) says: "This work shows the power of archaeology and ancient DNA working together to reconstruct human evolutionary history through time. We are currently expanding this approach to other transects across Europe."

Genographic Project director Spencer Wells says: "Studies such as this on ancient remains serve as a valuable adjunct to the work we are doing with modern populations in the Genographic Project. While the DNA of people alive today can reveal the end result of their ancestors' ancient movements, to really understand the dynamics of how modern genetic patterns were created we need to study ancient material as well."

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The above story is reprinted from materials provided by University of Adelaide.

Note: Materials may be edited for content and length. For further information, please contact the source cited above.

Journal Reference:

1.Paul Brotherton, Wolfgang Haak, Jennifer Templeton, Guido Brandt, Julien Soubrier, Christina Jane Adler, Stephen M. Richards, Clio Der Sarkissian, Robert Ganslmeier, Susanne Friederich, Veit Dresely, Mannis van Oven, Rosalie Kenyon, Mark B. Van der Hoek, Jonas Korlach, Khai Luong, Simon Y.W. Ho, Lluis Quintana-Murci, Doron M. Behar, Harald Meller, Kurt W. Alt, Alan Cooper, Syama Adhikarla, Arun Kumar Ganesh Prasad, Ramasamy Pitchappan, Arun Varatharajan Santhakumari, Elena Balanovska, Oleg Balanovsky, Jaume Bertranpetit, David Comas, Begoña Martínez-Cruz, Marta Melé, Andrew C. Clarke, Elizabeth A. Matisoo-Smith, Matthew C. Dulik, Jill B. Gaieski, Amanda C. Owings, Theodore G. Schurr, Miguel G. Vilar, Angela Hobbs, Himla Soodyall, Asif Javed, Laxmi Parida, Daniel E. Platt, Ajay K. Royyuru, Li Jin, Shilin Li, Matthew E. Kaplan, Nirav C. Merchant, R John Mitchell, Colin Renfrew, Daniela R. Lacerda, Fabrício R Santos, David F. Soria Hernanz, R Spencer Wells, Pandikumar Swamikrishnan, Chris Tyler-Smith, Pedro Paulo Vieira, Janet S. Ziegle. Neolithic mitochondrial haplogroup H genomes and the genetic origins of Europeans. Nature Communications, 2013; 4: 1764 DOI: 10.1038/ncomms2656
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