There are over 50,000 people in North America who define themselves as Hutterites, though you probably have never met one. One of the main branches of the Anabaptists, Hutterites live in self-sustaining communities throughout the rural northwestern United States and Canada.

Like their sister branches, the Amish and the Mennonites, the history and culture of the Hutterites have long fascinated scholars. But there have been few forays into the genetics of this unique community — until now. In the October 21 issue of the European Journal of Human Genetics, geneticist Irene Pichler and an international team of experts set out to unravel the genetic history of the Hutterites.

The history of the Hutterites goes back over 500 years, to a stretch of land in northernmost Italy called Tyrol. It was here that a small group of people, led by local hatmaker Jakob Hutter, formed a religious community centered on absolute pacificism and communal living. The Hutterites, as they came to be known, were part of the Radical Reformation, which rejected the teachings of both the Roman Catholic Church and the more moderate Protestant movement.

Due in no small part to their adherence to pacificism, the Hutterites soon became victims of persecution and expulsion. They moved several times to new settlements in central and eastern Europe. Their numbers dwindled significantly. By 1755, only 67 Hutterites were living in Transylvania.

By 1874, the Hutterites had had enough, and over 1,200 departed Europe for the rich farmland of western North America. They settled in present-day South Dakota, setting up several colonies. Today they are living much as they were upon their arrival in both the United States and Canada.

The Hutterites’ distinct and well-documented history over the past several centuries could make for an equally unique genetic history. Would traces of their history be etched in their genes? This is exactly what Pichler and her team sought to find out.

Pichler’s team focused on two segments of the human genome: the mitochondrial DNA and the Y chromosome. Because mitochondrial DNA (mtDNA) is passed down along the mother’s line, and the Y chromosome is passed down along the father’s line, the team could use both to paint a detailed picture of the Hutterites’ genetic history. The research team also analyzed DNA from several Central European groups for comparison, as central Europe is the Hutterites’ ancestral home.

Pichler proposed that the same constant reductions in population size that continually plagued the Hutterites, must also show up in their DNA. And that is exactly what happened. Among all the Hutterite DNA samples analyzed, the authors found only 11 distinct types of mtDNA (called haplogroups), and only 10 distinct Y-chromosome haplogroups. In other words, the Hutterites’ ancestral maternal and paternal lines trace back to just 21 individuals. This is an extremely small number of founders, and is further evidence that the large drops in Hutterite population size over the centuries are found in their genes.

Pichler and her team further discovered that the haplogroups among the Hutterites are vastly different from those found among central Europeans. For example, 30 percent of Hutterites belonged to a single haplogroup called X2c1 — which is virtually absent in Europe. This shows that even while the Hutterites lived in Europe, their genetics were vastly different from their non-Hutterite neighbors.

Centuries of isolation from the rest of Europe, followed by their massive migration to a new continent and continued isolation, have clearly defined the Hutterite people. And this study has revealed the history and genetics of this community as one of the most unique in North America.

Photo courtesy of Wikimedia Commons.

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The Near East – a swath of land that encompasses the Arabian Peninsula, the Levant, and everywhere in between – has been populated by humans longer than anywhere else in the world save Africa. It is where agriculture was born and spread into Eurasia. It is where the ancient civilizations of Mesopotamia and Egypt evolved and flourished. And it is where a particular paternal haplogroup, J1e, arose about 10,000 years ago.

Paternal haplogroups define a person’s all-male ancestry (i.e. the origins of your father’s father’s father, etc.), and are passed down from father to son via the Y chromosome. Haplogroup J1e has long interested experts because it seems to have expanded and flourished in the harsh deserts of Arabia. Today it is quite common among Bedouin nomads from Saudi Arabia, United Arab Emirates, and Oman, as well as in men from Turkey, Ethiopia, and the Levant.

In 2008, scientists at Stanford University proposed that the presence of J1e throughout the Near East could be tied to the nomadic hunter-herders who have dotted the region for thousands of years. In the October 14 issue of the European Journal of Human Genetics, these same scientists – including 23andMe consultants Roy King and Peter Underhill and 23andMe scientist Brenna Henn – test this theory with a little help from the field of linguistics.

The authors analyzed the DNA of more than 500 men from nearly 40 locations throughout the Near East. While many of these men belonged to haplogroup J1e, there were small genetic variations within J1e based on exactly where these men lived. For example, J1e samples from Turkey were slightly different from those in Oman.

When the authors examined differences among the ancient peoples of the Near East, they discovered that the languages spoken in different parts of the region were quite distinct. Until the Arabic swept across the Near East more than 1,000 years ago, there were dozens of languages spoken in the region: Aramaic in Syria, Babylonian in Iraq, and Canaanite from Lebanon to Jordan. The majority of these tongues are now extinct, but all belong to the same Semitic language family, to which Hebrew and Arabic also belong.

The authors reasoned that the history of these ancient languages may be tied to that of the people who spoke them. The history of these ancient people could be deciphered further by examining their genetic ancestry via paternal haplogroup J1e.

The researchers’ combined analysis of the J1e types and the ancient Semitic languages revealed some startling results. The authors found that J1e arose in Anatolia (present-day Turkey), expanding southward toward Arabia 10,000 years ago.

Limited archaeological evidence supports such an expansion, when hunter-gatherer groups, using bow-and-arrow technology and with the help of domesticated dogs, headed south into the heart of the Near East. Soon after they began expanding, the hunter-gatherers took up herding, domesticating animals like cattle and goats.

The linguistic evidence lends additional support. The common ancestor of all Semitic languages, called proto-Semitic, originated about 7,500 years ago, just as J1e was expanding. More importantly, the spread of proto-Semitic coincides with the spread of hunter-herders across the Near East.

So what does all this mean? The expansion of haplogroup J1e is closely tied to the expansion of the Semitic languages. And they are both linked to the expansion of hunter-herders, who journeyed from Anatolia southward into Arabia thousands of years ago. We now know just a little bit more about the ancient history of this fascinating region.

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There are many examples around the world of two distinct ethnic groups living side by side.

Sometimes these groups co-exist peacefully. Other times they do not.

Often two groups’ differences – along with circumstantial factors – lead to tension between them and sometimes violence. The Hutus and Tutsis of Rwanda, the Sunnis and Shiites of Iraq, and the Croats and Serbs of former Yugoslavia all illustrate how cultural distinctions – like language and religion – can contribute to tensions and conflict around the globe.

But do these cultural and ethnic distinctions translate to biological distinctions as well? Exactly how biologically distinct are two ethnic groups living side by side? Anthropologist Evelyn Heyer and an international team of researchers set out to answer these and many other questions by studying the adjacent – and culturally very different – Tajik and Turkic speakers along the Silk Road of Central Asia. Their results are published in this week’s BMC Genetics.

The authors focused on the Tajik and Turkic speakers because those groups offered a unique perspective on how two groups living in such close proximity can be so different from each other.

The Turks are largely nomadic herders. They speak Indo-Iranian languages like Azerbaijani, Turkish, and Altay. Their society is organized into clans, or “descent groups,” whose membership is passed down from father to children.

The Tajiks are, conversely, agriculturalists. They speak various dialects of the the Tajik, or Tajik Persian, language that may have arrived with Muslim invaders 1,000 years ago. Their society is largely patrilocal – meaning that when couples marry they put up residence near the husband’s family; and first cousin marriages are encouraged.

The two societies are supposedly closed, and members of both groups are said to rarely leave their clan or village. This cultural isolation made them perfect candidates for Heyer and her team to study.

So the researchers collected both maternally inherited mitochondrial DNA and paternally inherited Y chromosome DNA from more than 1,000 individuals spanning 24 Turkic and Tajik populations.

What they found was that these two ethnic groups weren’t so different after all.

Genetically, the Tajiks and the Turks were virtually indistinguishable. The authors found the overall level of genetic diversity between the two groups to be less than 1% overall — so small that there was a greater amount of diversity within each group than between the two.

Their analysis also shed some light on the origins of these these two ethnic groups. The modern-day people of Central Asia maintain their own origin stories that are unique to their particular group. In part, it is these unique origin stories that distinguish them from one another. But Heyer’s analysis proves that these groups actually share the same roots; they are simply a hodgepodge of the clans, tribes, and villages that have called Central Asia their home for thousands of years. Over many generations they banded together to form larger groups until they consolidated into just two major divisions: the Tajiks and the Turks.

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It may be you’ve heard a rumor that males are on the brink of extinction.

Whatever you may think of that prospect, the rumor is false. But over the past decade, numerous studies have hinted that the Y chromosome, a male necessity, is going the way of the dodo.

Though other studies have suggested this idea may be a bit of an exaggeration, a new report this week suggests that the Y chromosome may indeed be endangered.

In most mammals, such as us humans, two chromosomes determine the sex of each individual organism:  the X and the Y.  If an individual’s cells contain two copies of the X chromosome, then they will be genetically female.  If they contain one copy of the X and another of the Y, they will be male.

Yet even though these aptly named sex chromosomes have a similar duty — to confer sex — the X and the Y could not be more different.  The most striking difference between the two is their size; the Y is less than half as big as the X, and contains only 78 genes, compared to the more than 2,000 found along the X chromosome.  The evolutionary history of the two sex chromosomes and the question as to why they are so different from each other has been the subject of heated debate for many years.  Now scientists at Pennsylvania State University believe they’ve found a way to uncover not only the difference between the X and Y, but how and why it arose and what this means for the future of the small, but essential, Y chromosome.  Their results are reported in the July 17 issue of PLOS Genetics.

The research team, led by biologists Kateryna Makova and Melissa Wilson, believes the key to understanding the origins and future of the Y chromosome lie in some of our most distant mammalian relatives.  There are three classes of mammals: egg-layers like the platypus, marsupials like the kangaroo, and the eutherians, which includes humans and thousands of other similar species.  While there are many differences between the three groups, one of the most striking is the difference in the organization of the sex chromosomes.  As Makova explained, “In eutherian mammals, the sex chromosomes contain an additional region of DNA whereas, in the marsupials and egg layers, this additional region of DNA [is not on a distinct chromosome, but] is [a region of] the non-sex chromosomes.”

The authors argue that the key to the origins of the X and the Y chromosomes may lie in this fundamental difference.  By analyzing the X and Y of humans compared to the sex-determining regions of marsupials and egg-laying mammals, Makova and Wilson found that the X and Y split from the other chromosomes about 80 to 130 million years ago.

But that is not all they found.  The authors also examined how fast the X and Y mutated over time, and noticed a startling change that occurred at about the same time as the split.  “Our research revealed that the Y-specific DNA began to evolve rapidly at the same time that the DNA region split into two entities, while the X-specific DNA maintained the same evolutionary rate as it had previously,” Makova explained.

In other words, as soon as the X and the Y split their own distinct chromosomes, the Y began to evolve much more quickly than its counterpart, mutating at a much higher rate with each new generation.  The faster the Y evolved, the faster its genes disappeared.  Whereas at one point the Y may have contained thousands of genes, that number has dwindled to the mere 78.

The disappearance of these genes over time and the small number of those remaining on the Y begs the question:  will the Y chromosome ever disappear entirely?  The authors believed this was an important question to answer as well, and began additional analysis to determine the fate of the Y.

Makova and Wilson reasoned that there must be some utility to the Y, or else it surely would have disappeared by now.  As Wilson states, “we know that a few of the genes on the Y chromosome are important, such as the ones involved in the formation of sperm … .  Although there is evidence that the Y chromosome is still degrading, some of the surviving genes on the Y chromosome may be essential.”  By performing additional tests, they found that there were indeed some genes on the Y that will probably never disappear entirely.  But they also found several genes that were already disappearing, and were likely to be gone many generations from now.

Some recent studies have produced evidence that the genes on the Y may not be disappearing as fast as was initially thought. But, according to Makova, the Y chromosome may not be out of the woods just yet. “We still think there is a chance that the Y chromosome eventually could disappear,” she says.  “[But] if this happens, it won’t be the end of males.”  Instead, she believes that a new pair of sex chromosomes will arise from the genome, latching on to those few remaining genes, keeping alive the genes necessary for male survival.

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Only 250 miles separates the island of Madagascar from the southeast coast of Africa.  The short distance between the two land masses traditionally led the outside world to assume that the native inhabitants of Madagascar – known as the Malagasy – originally came from the west, probably from the present day southeast African nation of Mozambique.  Yet upon closer examination of the Malagasy’s language and their physical features, many scholars began to question this notion.  The Malagasy of the central plateau of Madagascar, known as the Highlanders, had light skin and facial features more akin to Southeast Asia or Indonesia.  They also practiced a rice culture that was not unlike the rice cultures of Asia.  And yet the coastal Malagasy, known as the Côtiers, seemed just the opposite.  They had darker skin and curly hair that was more similar to modern day Africans.

But both the Highlanders and the Côtiers speak the same language, which shares 90% of its vocabulary with a language spoken today in Southeast Borneo, and which has been officially classified as a branch of the Austronesian language family called West Malayo-Polynesian.  So how could a significant portion of Malagasy seem to share more in common with a region 5,000 miles away than they do with mainland Africa?  Trying to find the answers to these questions has vexed archaeologists, historians and linguists for generations.  Over the past several years, geneticists have entered the fray to try and unravel the mysterious origins of the Malagasy.  Their most recent effort appears this week in Molecular Biology and Evolution.

This study, led by Sergio Tofanelli of the University of Pisa, built upon a 2005 study by Matt Hurles and colleagues that was the first genetic exploration of the Malagasy people.  But Tofanelli and his colleagues wanted to dig even deeper into the genetic history of the Malagasy.  So they took the data analyzed by Hurles in addition to new DNA samples that were collected from people across the island of Madagascar.

They focused on two regions of the human genome often used in genetic ancestry studies:  the mitochondrial DNA (mtDNA) and the Y chromosome.  Because the mtDNA is used to trace maternal ancestry, and the Y chromosome to trace paternal ancestry, analyzing both in the same study can give a more complete picture of a group’s genetic history.

Tofanelli and his research team examined the mtDNA and Y chromosomes of Malagasy individuals scattered across the island, from both the Highlander and Côtiers groups.  They were searching for any clues that would give an exhaustive understanding of how and when the island of Madagascar was first settled, and by whom.

The researchers’ analysis revealed a mixture of both African and Asian genetic ancestry, in both the Highlanders and the Côtiers, which is perhaps contrary to the two groups’ physical apperance.  So what does this mean?  That even the Côtiers people, who often look more African in appearance, have an ancestry that traced back to Asia, specifically Borneo.  These results fit well with Hurles’ study and with what linguists have been saying for years; that the Malagasy language – while clearly tracing back to Borneo – also has some African elements that are significant.

The results from these analyses then begged the next question — how and when did the earliest inhabitants of Madgascar arrive on the island?  Was it in two separate migrations – one from the east and one from the west – or did the Asian/African genetic make-up of the Malagasy exist prior to their first steps on Madagascar?  It is easy to assume that any intermarriage between Africans and Southeast Asians happened after each arrived on the island.  In fact, Tofanelli describes the genetic make-up of the Malagasy as a consequence of “the encounter of people surfing the extreme edges of two of the broadest historical waves of expansion” in human history.  He is referring to the sub-Saharan African Bantu expansions that began 5,000 years ago and swept across Africa from Cameroon to Mozambique and southern Africa, and the Austronesian expansions about 4,000 years ago when seafarers journeyed from Taiwan to Borneo and beyond.

But Tofanelli proposes an alternative hypothesis as well.  He argues for a long history of contact between Bantu-speaking Africans and seafarers from Borneo dating back thousands of years.  As evidence he cites banana cultivation in Cameroon and Uganda that can be traced back to Southeast Asia, as well as the introduction of humped cattle into Africa from Asia.  If the Southeast Asians and eastern Africans shared farming techniques, it stands to reason that they may have shared genes as well.  Thus the people of Madagascar may have not simply been Africans and Southeast Asians arriving on the island from opposite directions, but rather they represent a more complex genetic history of proto-Malagasy arriving on Madagascar about 2,300 years ago, already containing a mixture of Asian and African ancestry.

This hypothesis most certainly needs additional evidence and data before it can be supported, but it brings a new level of understanding to the mysterious origins of the Malagasy.

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Science is dynamic and ever changing. As new research is published, theories get revised, and hypotheses retested. The field of genetic ancestry is no exception: The flurry of published research just in the last five years has been staggering, and we can now piece together the histories of many groups from nearly all parts of the globe. At the same time, a worldwide community of genealogists has seized upon this wealth of published research, combining it with their own genetic data to produce an even richer, more detailed human history.

We want our customers to have the most current information possible, so our scientists and engineers have spent the last several months updating the paternal lineages, or haplogroups, for all of our (male) customers. This has been quite a task, involving many layers of analysis and quality control to meet our standards of precision and accuracy.  The end result is a more detailed understanding of paternal ancestry for our customers.

The New Tree

Customers can find the 23andMe paternal haplogroup tree on the paternal line feature page.  It lays out the specific haplogroups for populations around the world, how they are related to each other, and how all men alive today can trace their paternal ancestry back to one individual who we refer to as the PoP (Poppa of all Poppas).  The organization of this tree is derived from more than 2,000 variable genetic markers, known as SNPs, on the Y chromosome. The particular combination of SNPs a man has determines which haplogroup his Y chromosome belongs to.

Finding the Right Tree

Over time enough additional SNPs are discovered, and there are enough revisions to the organization of other researchers’ Y haplogroup trees, that we must give our own a face lift to keep up. We used a variety of sources as a basis as we developed our new paternal haplogroup tree. We examined the published literature and spoke with experts in the field of Y chromosome genetic ancestry.  Perhaps most importantly, we used the wealth of information gathered from the International Society of Genetic Genealogy (also known as ISOGG).  This non-profit organization is run by genealogy enthusiasts who are passionate about discovering their family history through genetics. These enthusiasts, many of them 23andMe customers, have sifted through mounds of genetic data, both from the published literature and their own genetic profiles. The fruits of their labor are collected and organized in a haplogroup tree that is regularly updated at a high level of detail. ISOGG exists and prospers because so many genealogists are working together for a common goal.

We have worked primarily with the December 2008 ISOGG paternal haplogroup tree as a basis for updating our own.  Even since then, some paternal haplogroups been updated significantly.  So for these rapidly evolving haplogroups, we used the May 2009 ISOGG paternal haplogroup tree as a reference. The end result is a very detailed and up-to-date paternal haplogroup assignment for each of our male customers.

Your Paternal Haplogroup

What does this update mean for our customers?  For many it means a change in their haplogroup assignment. That change may be slight, or it may be more substantial.  For other customers it means no change at all.  When examining your new paternal haplogroup, it is likely you will see one of the following differences:

1) A more specific assignment:  Because the new paternal haplogroup tree examines many more SNPs than the original, we are able to give our customers more precise assignments. As a result, it is possible that your new haplogroup assignment may be longer and more specific than the original.  For example, customers who were assigned haplogroup J2a1 will now be reassigned to haplogroup J2a1a.

2) A more specific and slightly different assignment:  This category of change is by far the most common affecting our customers, because the organization of the haplogroup tree has changed. Therefore someone’s new assignment may look similar to their old one, but it will be longer and/or slightly different. For example, a customer who was assigned to R1b1c may now be reassigned to R1b1b2.

3) A completely new letter assignment: This is the rarest of the changes that will likely occur, and is also due to a reorganization of the paternal haplogroup tree over the past few years. For example a customer currently classified as K2 will now be reassigned to haplogroup T.

It is important to note that your ancestry has not changed, only your haplogroup assignment. But because this update has allowed us to define many more haplogroups than we had originally, we can give even more specific information about our customers’ paternal ancestry.  In the coming weeks, we will be updating the summary pages for our haplogroups with this additional genetic history.

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My surname — Holden — has gone through many incarnations since it originated in England nearly 700 years ago.  Letters were added, then dropped.  Some branches of my family added an extra “u” in the middle, while others changed the pronunciation entirely.  Then, when my ancestors arrived in America over 200 years ago, the name went through a whole new set of changes.  It seems my surname has been in a constant state of change since its inception.

But the story of my surname is not unique.  Millions of Americans have similar stories about ancestors who, upon arriving in the New World, actively changed their names to sound more “American.” German immigrants named Blum became Bloom, Küsters became Custers, and Kÿfers became Coopers. Immigrants from Italy, Sweden, France, and countless other countries underwent similar transformations.  After just a few generations, the original spelling or pronunciation was lost.

Just as our surnames have changed over the centuries, little by little, so too has our DNA.  In fact, some regions of the human genome acquire mutations in such a way that researchers can trace the changes back through time – much like tracing a surname back for generations in a family tree.  And one region in particular, the Y-chromosome, happens to be passed down from father to son, the same way surnames are inherited in Western culture. That provides a wealth of opportunities for scientists from a variety of disciplines to use the Y-chromosome to unlock history’s secrets, unravel family trees, and even solve crimes.

The Genetic Legacy of the Vikings

The histories of Scandinavia and the British Isles have been entwined since Vikings from Norway and Denmark landed on the eastern coast of England in the year 792.  Successful raiding parties eventually led to settlements along the eastern half of England.  Today there are remnants of Viking settlements in this region in the form of place names, unique vocabulary, and even surnames.  Last year, British geneticists took surname information from an area formerly settled by Vikings to see if men living there today who had Scandinavian surnames also had evidence of Scandinavian (aka Viking) genetic ancestry.  They analyzed the Y-chromosomes of several hundred men, and, not surprisingly, found that those with Scandinavian surnames did indeed have Scandinavian DNA, at least on the Y-chromosome.  Similar studies of Irish men have also found a modest connection between surnames and Y-chromosome types.

Surname DNA Projects

As we reported several weeks ago, the field of genealogy has been invigorated by the increasing use of genetic testing to fill in the missing branches of a person’s family tree.  Genealogists are now comparing their Y-chromosomes to those of others with the same surname, to see if a shared surname is also an indication of the shared ancestry.  Within the past few years, surname DNA projects have sprung up all across the world – with hundreds of genetic genealogists digging deep into their genes as they piece together their detailed family trees.

Surnames and Forensics

By far one of the most interesting applications for surname and Y-chromosome comparison is in the field of forensic science.  In 2006, British geneticists found that – for some of the more rare surnames such as Maloy or Rivis, there was a strong connection between surname and Y-chromosome haplogroup.  The authors reasoned that, if DNA were to be recovered from a crime scene, forensic investigators might be able to narrow down the possible perpetrators to a specific subset of surnames.

However, there are several limitations to this idea – namely the fact that most men in the UK have rather common surnames, such as Smith, Green, and Adams.  Men with these surnames have a wide range of Y-chromosome DNA types, so it would nearly impossible for investigators to use the Y-chromosome to locate a suspect.  However, on principle this idea has merit, and further advances along these lines may someday allow investigators to exploit the DNA-surname connection.

One final note: 23andMe customers need not worry that their data will be used in this way — our research database does not include surnames and our terms of service do not allow us to share data with law enforcement unless we are legally compelled to. And even if such a situation did arise, we have publicly committed to resisting legal requests for customer data.

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Before genetics came into the picture, researchers interested in the introduction of agriculture to Europe had only the archaeological record to go on — a limited collection of primarily stone and bone artifacts that left much room for interpretation. But as researchers began applying population genetics to the question of how farming spread across Europe, beginning with the work of Luca Luigi Cavalli-Sforza nearly 40 years ago, there began to be hope for a better understanding of how agriculture spread through the continent beginning about 10,000 years ago.

Decades of genetic research have produced some clarity. But geneticists have also created their own new sources of new debate surrounding the spread of agriculture.

Over the years, two schools of thought have jockeyed for dominance: one argues that farmers from the Near East came into Europe around 10,000 years ago, spreading both their knowledge of farming AND their descendants throughout the continent.  Known as the ‘Demic Diffusion Model’, this hypothesis predicts that the majority of today’s Europeans trace their ancestry to early farmers from the Near East.  The alternative hypothesis, dubbed the ‘Cultural Diffusion Model’, argues that while the practice of farming likely spread from the Near East into Europe, the farmers themselves did not.  Instead, the technology was passed along from settlement to settlement, until it reached northern Europe 5,000 years later. It predicts most modern Europeans should trace their ancestry to the original Stone Age inhabitants of Europe.

As the debate has continued, newer studies have begun breaking the puzzle down into more manageable pieces, looking at particular regions within Europe to see how farming changed the demographics on a more regional level.  This is exactly what new research published in the European Journal of Human Genetics seeks to do, by examining the genetic history of the Balkans in Eastern Europe in an effort to work out what was happening there nearly 10,000 years ago.

The authors of the study, including Stanford professors and 23andMe scientific advisers Drs. Peter Underhill and Roy King, focused on the Balkans chiefly because the archaeological record in this area hints at interactions between farmers from the east and the hunter-gatherers who were already living there.  The researchers chose to examine the Y-chromosome, which is passed down from father to son, to see if any traces of such interactions remained in people living in the Balkans today.  They sampled more than 1,200 men from Greece, Albania, Slovenia, and many other countries on the Balkan Peninsula and throughout Eastern Europe.

What they found were three major Y-chromosome haplogroups (clusters of men who share deep ancestry along the paternal line). One group pre-dated the arrival of agriculture into the region, a second arrived along with agriculture, and a third fell somewhere in between.

Specifically, more than 60% of those sampled belonged to branches of either haplogroup I or haplogroup R, both of which are believed to have arrived in Europe tens of thousands of years ago.  In addition, a unique branch of haplogroup E is found at levels of 15-25% among the men tested, but only in those people hailing from the southern Balkans (such as Greece or Macedonia).  Finally, up to one-fifth of the men tested fell into haplogroup J, which is common in the Near East and thought to be closely associated with both Mediterranean seafarers and the origin and spread of agriculture.

What do these figures mean?  First of all, it is clear that over half of the men in the Balkans and Eastern Europe belong to haplogroups that pre-date the arrival of agriculture in the area.  These mens’ paternal ancestors likely trace back to the Mesolithic hunter-gatherers.  On the other hand, the 20% of men belonging to Haplogroup J likely trace their ancestry to the same Near Eastern populations where agriculture originated.

So it stands to reason that – because the authors’ samples contain both hunter-gatherer and farmer haplogroups – there was likely some kind of interaction between the two populations when they came into contact with each other nearly 10,000 years ago.  More importantly, it reveals that the spread of farming into Europe cannot be pigeonholed into either the Demic Diffusion or Cultural Diffusion Model.  Its spread is far more complex – and intriguing – than many initially thought.

But what about the men who traced their ancestry to that sub-branch of haplogroup E, which is typical of North or East Africans; what is it doing in the Balkans?  Haplogroup E has a unique history, stretching back some 40,000 years to East Africa. From where men carrying it expanded into the Nile Valley.  The authors believe this branch of Haplogroup E exited Africa almost 16,000 years ago, well before the arrival of farming, making it to the southern Balkans a few thousand years later.  Men bearing the haplogroup may have been among the first converts to agriculture when Neolithic farmers arrived in the area a few thousand years after that.

So it would seem that by using genetics to piece together ancient interactions between Mesolithic hunters and Neolithic farmers, we are actually left with new questions surrounding the arrival of Haplogroup E.  Who were these men who carried it?  What made them expand from the Nile Valley into the Balkans, just prior to the arrival of farming?  And did their presence in the Balkans influence interactions between the hunter-gatherers and the farmers from the Near East?  Once again, research into the genetic signatures of the first farmers has given us both new answers, and new questions.

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The American Society for Human Genetics (ASHG) has released a statement outlining a set of recommendations for genetic ancestry testing.

At a press briefing on Thursday, members of the ASHG Ancestry Testing Task Force Committee discussed two main themes: the need for clear communication about the limitations of genetic ancestry testing, and the need for researchers and companies doing this type of testing to engage with the social sciences to put results in context.

Michael Bamshad of the University of Washington School of Medicine discussed at length the need for people to understand that ancestry assignments based on genetics are inherently uncertain and can be affected by several factors, including the reference populations used in the analysis, the type and number of genetic markers analyzed, and the statistical methods employed.

ASHG president Aravinda Chakravarti further emphasized that questions about the “accuracy” of genetic ancestry testing are aimed at the interpretation of the genetic data, not at the actual DNA analysis.

Task force co-chair Charmaine Royal of the Duke University Institute for Genome Sciences and Policy addressed the committee’s concerns about the psychological impacts of genetic ancestry testing, especially as related to issues of identity.

23andMe Senior Director of Research Dr. Joanna Mountain had a chance to talk with some of the members of the ASHG Ancestry Testing Task force about their statement.

“Members of the panel emphasized to me that their primary goal was to raise a set of concerns around identification of ancestry through genetics,” said Mountain.

“Because several of us at 23andMe were previously aware of these concerns, we developed our ancestry features with those concerns in mind. For instance, we consider a large number of markers for all the chromosomes of the human genome, including the mitochondrial genome. We also avoid being overly precise in reporting an individual’s ancestry. And we are currently creating educational tools to help our customers understand how genetic information can be informative about ancestry.”

The speakers stressed several times that their statement was not aimed just at consumer companies offering genetic ancestry testing, but also at academic researchers in the field.

Unfortunately, Mountain said, the ASHG guidelines leave out some of the potential benefits of ancestry genetic testing.

“For instance, ASHG President-Elect Ed McCabe encouraged the audience to ask their family elders about family history over Thanksgiving, as an alternative to learning about ancestry through genetics. But individuals who have signed up for 23andMe’s service may find themselves far more motivated to discuss family history than they would before seeing their genetic data.”

For a more thorough analysis from a genetic genealogist’s point of view, click here.

McCabe said the statement released this week is a preliminary document. The committee expects to issue a more detailed report in Spring 2009.

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About 3,500 years ago the Phoenicians expanded from their homeland in present-day Syria and Lebanon, using their superior maritime technology to establish trading posts across southern Europe and North Africa. They traded silver from Iberia, copper from Cyprus, and textiles from Morocco. They built cities in Sicily, Malta, and Tunisia that rivaled those in Greece and Rome. But by the 1st century BC, nearly all evidence of their power and authority over Mediterranean trade routes had vanished.

The Phoenicians’ fate as a maritime power is well documented. The Persians conquered the Phoenician homeland in 539 BC. Two centuries later, Alexander the Great’s army swept in from the west. Finally, the Roman Empire conquered – and destroyed – the Phoenician city of Carthage in 146 BC following the Third Punic War.

But what happened to the Phoenicians themselves? Were they, too, wiped out? Or are their descendants still alive today?

In a study published this week, researchers identify Phoenician-specific DNA markers in present-day Mediterranean populations, demonstrating that genetic traces of the ancient civilization still exists some modern-day peoples. These people could be descendants of the Phoenicians themselves.

Using genetics to trace specific historical migrations such as the Jewish Diaspora, the Norman invasion of Britain, or even the Viking expansions into Western Europe, has always been difficult. Attempting to trace migrations across the Mediterranean is even more arduous, as there have been multiple migrations at different times throughout history. How do scientists sort out each unique migration event over the long and complex population history of the region? A team of geneticists from National Geographic and IBM’s Genographic Project believes they have found a way to do just that. They discuss their research in the latest issue of the American Journal of Human Genetics.

Traditionally when scientists want to understand the genetic history of an area, they collect DNA samples from the entire region of interest. But in this case the authors of the AJHG paper collected samples from specific towns and cities that are believed to be built on or near ancient Phoenician archaeological sites, including Carthage, Cyprus, and Sicily. They reasoned that if descendants of the Phoenicians do indeed exist, they would more likely be found near these sites.

Armed with this newly collected data, the authors focused on the Y-chromosome to trace the Phoenicians’ genetic history. According to Chris Tyler-Smith, one of the study’s authors, “We chose the Y-chromosome because its male-specificity means that it would have been carried by the predominantly male Phoenician traders.” They then used a newly devised analytical method of distinguishing any Phoenician migration from other geographically similar migrations. Their results are surprisingly informative.

The authors found a weak – but significant – genetic signature among their samples that could not be explained by chance. Many of the samples belonged to a very specific branch of haplogroup J2, which the authors believe points back to distinct migrations by Phoenician traders from the Middle East into Europe and North Africa more than 3,000 years ago.

The applications of the authors’ new approach to studies of population history are incredibly far-reaching. Perhaps similar analyses could be used to trace the genetic footprints of Alexander the Great and his army into Persia during the 4th century BC, or migrations along the Silk Road from China during the Middle Ages. The authors even propose that their technique could be used within populations, to discover historical migrations that we never even knew existed.

Photograph courtesy of Wikimedia Commons.

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