For the English names that have survived with very few holders, there is a strong link between the name and the bearer’s Y chromosome. In fact, the less common the surname is, the more likely it is that any two men with that name have a similar Y, as is the case within name groups like Werrett, Titchmarsh, and Attenborough. The Attenborough men are the most homogeneous of them all; 87 percent of them have descended from a single man and share the same Y chromosome, which is found in only 1 percent of the rest of the population.
So strong is the link between the surname and the Y in such cases that it’s been suggested that, for many of England’s unsolved cases of murder and rape in which a Y DNA sample has been taken from the scene but no suspect has been identified, the Y profile could be matched against a database of Y + surname matches, generating a list of possible names for the bearer of that Y and significantly narrowing the pool of suspects.
In Ireland, by contrast, a man is thirty times more likely to share the same short repeats on his Y with another man of the same name than with a man of a different name, regardless of how popular that surname is. The surname Ryan, for instance, is held by approximately 1 percent of the Irish population (Smith is held by 1.3 percent in England), yet there’s a forty-seven-times-greater chance that any two men who are called Ryan will have the same Y than any two men who are chosen at random.
Even though there are sixty thousand Irish Ryans, researchers believe that many of them have a Y in common because when surnames began, there were only a few, and perhaps even only one, Ryan. This could mean that most of the many Ryans of modern-day Ireland descend from this founder. The O’Sullivans, O’Neills, Byrnes, and Kennedys all appear to have had a dominant founding Y as well.
The Kellys and the Murphys are more like the Smiths. While two random Kelly men are 4.5 times more likely to share a related Y than they would with a non-Kelly, there are many clusters of men with different Y chromosomes within the Kelly name, as there are among the Murphys. It’s likely those surnames were more ubiquitous early in the country’s history. The McEvoys, for their part, apparently had two dominant founding Y chromosomes, a theory that is supported by records revealing that when the name was anglicized, two ancient families, the Mac Fhiodhbhuidhes and the Mac an Bheathas, were drawn in under the same banner and both became McEvoys. History also indicates that fully three Irish surnames—McGuiness, Neeson, and McCreesh—are all anglicizations of the same Gaelic name Mac Aonghusa (son of Angus), which DNA evidence confirms, as all three groups overlap strongly on one Y.
Surname patterns in England and Ireland emerged in the landscape where surnames were invented, but in the United States only Native American names have not been imported. Nevertheless, patterns of immigration and neighborhood formation in the New World can be illuminated by what we know about the origins of the surnames of the people who settled there. In the absence of other information, you could make a good guess about the antecedents of much of the modern populations of the United States, Australia, and Canada from their single most common surname—which, again, is Smith.
• • •
At the Highland Games I met Glynis McHargue Patterson, a MacLaren by marriage and an administrator of the McHarg/McHargue YDNA Project.
A few years ago she was contacted by a man called McHarge who lived in Canada. He had been born in Knoxville, Tennessee, and he knew his grandfather had lived there but he couldn’t discover anything about his family beyond this. Glynis found the man’s grandfather using census records and traced him back through the male line to an Anne McHarge, who lived in a small town in the mountains of Tennessee in 1850. But the trail ended there; she could find no trace of Anne’s husband. Where was the missing Mr. McHarge?
With more research Glynis learned that there was no missing male McHarge: Anne never married, so McHarge was her maiden name. Glynis suggested that the Canadian McHarge take a Y-chromosome test. He would not have a match in the McHarg/McHargue YDNA Project, because, of course, Anne didn’t have a Y chromosome to pass down. Still, he might get some more clues about where his paternal line came from.
The man took the test, and Glynis was right—he did not match the McHarg/McHargues. Curiously, though, he came up with two sixty-six of sixty-seven marker matches to another family tree DNA surname project for the name Bieble. Glynis went back to the records and one day realized that the family who lived two doors down from Anne McHarge were called the Biebles, and they had a seventeen-year-old-son. She encouraged the Canadian to get in touch with the Bieble surname project administrator and ask him about it.
It wasn’t long before the two men had come up with a likely explanation. Indeed, the Canadian’s Y was most definitely a Bieble Y, and the administrator, who knew a great deal about the family history, confirmed that the reputation of his ancestor, the seventeen-year-old neighbor, had lasted as long as his Y. Anne McHarge’s neighbor, the Canadian told Glynis, was known as something of a ladies’ man.
Confirming the Bieble connection meant the Canadian not only learned about the male side of his family but was also, because he connected with the Bieble project, able to look back much further in his genealogy. He was beside himself, said Glynis, who added that genealogical detective work consists of “genealogy, genetics, and . . . pure dumb luck.”
Since I started spending time with detectives of the personal past, I’d heard quite a few stories about the role historical neighbors sometimes play in cold-case illegitimacies (which genealogists politely refer to as “nonpaternity events”). How often did such births happen? For a long time the estimate was 10 percent in every generation—a figure that has been used to, among other things, discredit all of genealogy. Based on his own Y research, Bob McLaren believed that 10 percent was too high, and since academic researchers began to investigate Y and surname patterns, their findings have backed him up. A number of different studies have converged on a number of well under 5 percent and much closer to 1 percent. The long-term effects of even that low a figure could still be significant, but it’s hardly enough to discredit all documentation.
• • •
The patterns created by surnames and Y chromosomes are still being investigated, and the role that different social and biological forces play must be untangled. So far it seems that even if a surname group overwhelmingly shares one kind of Y, it doesn’t necessarily mean that the Y belonged to the first male to take the name. It’s possible that other Y chromosomes were introduced into the family, perhaps even hundreds of years after the surname was founded, and were more successfully reproduced over the generations until they came to dominate. For example, there’s only a 10 percent chance that the dominant Y in the Attenborough group is the Y of the original Mr. Attenborough. It’s more likely to have come from a more recent and rather successful inductee.
In Ireland researchers found that for all the surnames they examined, even when there was one dominant Y, it was only ever held by half of the modern subjects, at best. That means that all the surname groups are groupings of different Y chromosomes. The variable topography within the modern Y/surname groups is a testament to the dynamic forces that have shaped people’s lives over time. In addition, adoptions, illegitimacies, and other unique interactions affected the journey of the name and the Y through time. And that’s just the Y.
Once you start following the pattern made by one segment of the genome through time, you realize that even though chromosomes are transmitted as a package, twenty-three from each parent, the smaller segments of DNA that a chromosome is composed of can travel quite separately from one another. Mitochondrial DNA is like the Y, because a mother’s mtDNA is not recombined with a father’s, so the father’s is not passed down and the mother’s goes to all her children. If she has lots of daughters, it spreads out from there.
The journey of the X chromosome is unique too. If a woman has a son who has a daughter, then her X does a funny kind of hop through the generations. My sons get an X ch
romosome from me, which is a mix of the X chromosomes I got from both my parents. If one of them has a daughter and passes his X on to her, it won’t be reshuffled. Remember, his X is paired with his Y, and the Y does not recombine, so for this one generation, the X behaves a little like the Y.
My future granddaughter—let’s call her Trixie—will have an X from her father and an X from her mother. Here’s where the skip-hop comes into it: The X from Trixie’s mother is a mix of Trixie’s mother’s parents, but the X from Trixie’s father is a mix of his mother’s parents, making Trixie ever so slightly more like some people who are three generations back on her father’s side than she is like the same people on her mother’s side. Or, to put it another way, Trixie’s paternal grandfather contributes nothing to her X.
The separate lives led by these different segments of DNA give us a glimpse of the fine-grained social processes and physical interactions that together add up to form the genomic history of the world. They force us to contemplate how alike we are and how unique we are. Above all they underscore how brief our personal moment in that history is. I once read that the flow of genes through time is like a great river, and individual lives are just eddies in the stream. When an eddy forms, the current is paused for a microsecond, and there we are—an assemblage of many different bits from many different sources—and then the stream pours on, and all those bits go forward in time, except that we no longer travel with them.
Apart from the Y and X chromosomes, the rest of the genome is called the autosome. These twenty-two chromosome pairs are the ones that get recombined before they are passed on. As scientists have developed different ways of analyzing the autosome, more and more ordinary people are beginning to access the secrets inside their own autosome, as well as larger truths about the human network.
Chapter 10
Chunks of DNA
Study the past if you would define the future.
—Confucius
On a winter’s night in Utah in 1999, Scott Woodward’s phone rang at 2:00 a.m. The father of four teenage sons, Woodward leaped to answer it and heard an older man at the other end ask, “Is this Scott Woodward?” Then, “Do you know anything about DNA?” Woodward was, in fact, a professor of molecular genetics at Brigham Young University. The caller said his name was James LeVoy Sorenson. He was from Utah but had traveled to Norway in search of his ancestral origins; he was trying to find a connection to the past, but he wasn’t getting very far. Sorenson wanted to know whether Woodward would be able to analyze the DNA of every individual in Norway for him. And if he could, how much would it cost?
Woodward, a pretty laid-back guy, said he’d think about it and he agreed to call Sorenson in a few weeks. He went back to his lab, and he hunted down some people who had worked for Sorenson. “Is this guy for real?” he asked. “Well, he’s been known to do crazier things,” was the reply. Indeed Sorenson was the richest man in Utah and one of the richest men in the world. He’d founded thirty-two different companies, personally held sixty patents, and in his lifetime had made well over a billion dollars. The consensus seemed to be that Sorenson’s projects tended to involve big ideas that cost a lot of money—and sometimes made a lot of money in return. One of these ideas was the disposable surgical mask, which Sorenson invented in the 1950s.
So Woodward thought about it. How much would it cost to analyze the DNA of everyone in Norway? How many people lived in the country? How could he obtain a blood sample from each one of them, and how much actual blood would that be? These were compelling questions, but Woodward wasn’t entirely comfortable with them. It was one thing to spend millions of dollars analyzing the DNA of an entire country, but it was another to determine if it was a worthwhile exercise. Would taking all that time and employing all those people be the best use of Sorenson’s money? Did the project have merit as well as ambition?
Of course, all professional scientists have to be budget conscious, as there’s only so much research funding to go around, and in order to get any of it, they have to show they can do more with it than the next lab jockey. But even if scientists weren’t competing for financial resources, they would—by nature—be cautious with them. The essence of all successful research involves wringing the most knowledge from the fewest experiments, and Woodward wasn’t clear about how much knowledge was enough to justify an undertaking of the scope of Sorenson’s proposal.
At the same time that he began putting together an estimate for the Norway project, Woodward started working on a second idea to propose to Sorenson. Woodward’s study would cost the same amount of money but would give Sorenson—and the world—a lot more genetic bang for their eccentric-billionaire buck. Still, he assumed that neither project was likely to get off the ground, as the money that would be necessary was, as far as genomic analysis went, a completely unprecedented amount.
Two weeks later Woodward sat at Sorenson’s desk, and Sorenson asked how much it was going to cost him to genotype Norway. “Well, I can tell you what it will cost you,” said Woodward. “But you can’t afford it.”
“Oh, really?” said Sorenson. “How much would that be?”
“It will cost you half a billion dollars.”
Sorenson shrugged. “I can do that.”
Whoa! Woodward thought. I have set my sights way too low.
• • •
Around the time that Sorenson called Woodward, the wider world was just becoming aware of the extraordinary potential of DNA. For some years scientists had been working out how to trace the movements of long-dead people through the Y chromosome, and it was becoming clearer that if you knew how to read it properly, the DNA of even a random set of individuals could open up tracts of human history that had been entirely obscure. For exceptionally savvy observers like Sorenson, the letters of DNA must have looked like the proverbial bread crumbs, scattered by individuals in the past as they wended their way around the planet.
What was even more striking about this new way of looking into the past was the fact that individuals had a fundamental role to play in it. Genetic history didn’t just survey the broad strokes of history and the lives of a few notable individuals—it built the picture up one human being at a time. This meant that not only could you see far back into the history of the world, but you could also see where your DNA came from and, indeed, traces of who you came from in it.
Where Sorenson’s project was concerned, Woodward explained that analyzing the genome of everyone in Norway would only reveal so much. It would tell a lot about the history of Norway, and it would tell Sorenson where he fit into it. But for the same half billion dollars, Woodward said, they could answer not only Sorenson’s personal question but also many, many more at the same time.
Woodward proposed instead that they analyze the genome of two hundred individuals from each of five hundred different populations around the world. That collection of 100,000 genomes would form a microcosm of the human race. The DNA would be representative not just of everyone alive today but also of a massive fraction of everyone who had been alive, particularly in the last few hundred years. The goal, Woodward explained, was not just to analyze and match up the DNA of that many people but to get at least four generations of family history from each person as well. They were going to use science to personalize history. But first they had to ask 100,000 people for some blood.
For not entirely coincidental reasons, it turned out that Utah, with its massive holdings of genealogical data, was the best place in the world for anyone to have this kind of idea. The team started with the “low-lying” fruit at Brigham Young University, explained Woodward, who put some of his students onto the project. “Everybody that is currently in Utah was not in Utah 160 years ago, so their ancestors weren’t here, other than the Native Americans. So when you combine genealogical information with the DNA information you get out into lots of different places very rapidly.” In the first couple of weeks they had collected three thousand samples of bl
ood, and within a year they had collected ten thousand, each with two hundred to three hundred years of genealogical and geographic information attached to it.
When I visited Woodward’s lab in Salt Lake City twelve years after his call from Sorenson, I asked him how he had taken the project beyond the small city near the Great Salt Lake and convinced people to participate. Once they had exhausted Utah’s diversity, he said, they had capitalized on the Family History Centers of the LDS, which were all over the world. They also approached genealogical societies.
Woodward’s team asked people to donate their DNA as an act of philanthropy. While the study was independent of the LDS, it must have helped that the church already had well-established patterns of charity based around family lineage. Indeed, James LeVoy Sorenson’s objective in traveling to Norway in the first place had been to find ancestors to whom he could offer church membership.
As large as the Family History Center network is, it does not contain data for the entire world, so once Woodward’s team exhausted the church network, they had to find populations who weren’t just willing and interested but whose history was telling in some way. They went to Africa and collected 10,000 samples. They went to Asia and Kyrgyzstan and many other countries. One of their earliest trips was to Mongolia, a major crossroads for the Silk Road, where they collected three thousand blood samples.
Woodward’s organization, the Sorenson Molecular Genealogy Foundation, was one of the first genetic genealogy companies. It eventually acquired more than 100,000 samples of DNA from all over the world. SMGF analyzed Y chromosomes and mtDNA, which for that era was an incredibly expansive survey. Still, such is the speed of change in this field that what they accomplished looks limited in comparison to what we have today. SMGF was sold in 2012 to Ancestry.com, the biggest genealogy company in the world. Since its acquisition, the original project has grown even beyond the epic vision of the Mormon billionaire. Scott Woodward now heads up a group that links millions of documented lineages with more than 700,000 spots on the genome, including autosomal DNA along with Y DNA and mtDNA.
The Invisible History of the Human Race Page 24