DNA USA

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DNA USA Page 33

by Bryan Sykes


  Between our meeting in New York and the approaching rendezvous in Boston, I had read up on Dr. Gates and soon realized quite what a prominent and highly regarded individual he was. He is foremost a scholar, the author of fourteen books so far, including The Signifying Monkey, a theory of literary criticism that went on to win the American Book Award, and The Trials of Phillis Wheatley, an appraisal of America’s first published black poet. However, he has always had a great personal interest in genealogy, and his highly acclaimed television documentary series introduced him to an audience far beyond the narrow confines of academe.

  Gates could not have been more accommodating when Ulla and I met him at the Du Bois Institute in Harvard. He took us on a whistle-stop tour of the institute, where we saw the world’s only hip-hop archive, with recordings, memorabilia, and even the footwear of famous rap stars, and, in separate libraries, a fabulous collection of African and African American art, including one project titled The Image of the Black in Western Art. I met his staff, again extremely helpful, and all clearly devoted to Gates. Next we dashed to his house to check on his own DNA results. He had already had his chromosome portrait painted and also his mitochondrial DNA and Y chromosomes analyzed. There wasn’t time for me to look in detail, but I did immediately recognize from the mutations in his mitochondrial DNA that we were both members of the same clan and closely related through our maternal ancestors. No wonder we were getting on well. To Ulla and me he was completely charming, open and extremely helpful. He had enjoyed The Seven Daughters of Eve and, in a very gracious gesture, offered to put my name forward for a fellowship at the institute, an offer that I gratefully accepted.

  Gates is well known across the United States as the host of the successful PBS documentary series African American Lives (2006), African American Lives 2 (2008), and Faces of America (2010) in which I made a brief appearance. In these shows Gates introduces a number of prominent Americans to their own ancestry. He was quick to realize the special place that DNA can play in connecting African Americans to Africa and injected that element into all three programs. The genetic component of the most recent program had been helped a great deal by the proximity at Harvard to the Broad Institute, a high-throughput DNA research facility founded by two luminaries of genetics, Eric Lander and David Baltimore, which is devoted to untangling the genetics of common disease. I had known these two distinguished scientists as champions of the human genome and also a third, George Church, a professor of genetics at Harvard Medical School who was affiliated with the Broad. Through his membership of Church’s Personal Genome Project, Gateses junior and senior were the first father and son, and the first African Americans, to have their entire genomes sequenced. Since then, the Du Bois Institute has gone on to cosponsor the Roots into the Future initiative, a large-scale program of genetic testing, directed specifically at African Americans, that is searching for sophisticated correlations between genetics and treatment in this community that has, thus far, been distressingly underrepresented in the genetics data.

  In African American Lives Gates employs mitochondrial and Y-chromosome tests on his guests in a way that is familiar to us. He also used the AIMs markers to estimate the ethnic composition of their genomes. Remember that when these documentaries were made, in 2006 and 2008, chromosome painting was not available. Even so, I was keen to ask Gates about himself, his experiences making the shows, how his guests had reacted, and lots of other things. We met over dinner with some of his colleagues from the faculty. The location was the Charles Hotel on Harvard Square, and the diners, other than Dr. Gates, Ulla, and me, were Marcyliena Morgan, an anthropologist, a professor of African and African American Studies, and the director of the hip-hop archive; Lawrence D. Bobo, W. E. B. Du Bois Professor of the Social Sciences at Harvard and a member of the prestigious National Academy of Sciences; and Evelyn Brooks Higginbotham, a professor of History and chair of the Department of African and African American Studies. On paper, this was a high-class academic gathering with more degrees around the table than pieces of cutlery. However, it was no dry encounter but one where serious discussion was punctuated by witty repartee and loud peals of laughter. Ulla and I have rarely had such an entertaining evening.

  I had prepared a list of questions in my notebook. The first of these referred to Gates’s own DNA. As mentioned a short while back, he and I are closely related through our mitochondrial DNA. That is not because I have an African matrilineal ancestor, but because Gates is a member of one of the seven European clans and shares my clan mother, Tara. It is quite unusual for an African American to have a European mitochondrial DNA, but that was not the point of my question. Rather, it concerned the way this news was relayed to him by the lab. One of the first things people want to know when they get their DNA results, naturally enough, is who they match and where their newfound relatives are from. When Gates had asked this question, he was told he had a match in Nubia, a region of Sudan on the River Nile to the south of Egypt. What he was not told was that he also had hundreds of other matches in Europe, which is no surprise for a descendant of Tara. I was interested in the reason for this omission. When Gates saw a map of the Old World with his mitochondrial DNA matches marked on it, sure enough there was one red spot in Nubia, but to the north and west, the spots were so dense that, in his own words, “it looked as if Europe had smallpox.” So why was he not told about these genetic matches in Europe? When he challenged the lab, not the Broad on this occasion, they said that they thought he might be disappointed. “Were you?” I asked. “No, not at all,” he replied, but it still struck me as interesting that the lab thought he might have been.

  We then moved on to how African Americans reacted to discovering the extent of their European ancestry. It is very unusual for them to have non-African mitochondrial DNA, but very common for African American men to carry European Y chromosomes, which roughly a third of them do, as we have seen. In my conversations with Gina Paige and Rick Kittles, they were very aware of the potential for disappointment that people felt when confronted with this particular piece of news. That chimed with my much more limited experience when I had been asked to do the same test on some Afro-Caribbean celebrities in Britain for a BBC documentary, Who Do You Think You Are? In one case I remember, a top-class athlete had an obviously European Y chromosome, but the producers kept that from him and it was never shown. Yet Dr. Gates’s view was that it really didn’t matter all that much and that African Americans would, or should, be very comfortable with discovering that some of their ancestors had European roots. Behind his answer was, I think, one of the founding principles of the Du Bois Institute that is so central to Gates’s vision: African American culture was not merely African across the Atlantic but a separate culture, worthy as a subject of scholarship in its own right, irrespective of the identity of the scholar or student. In other words, you didn’t need to be an African American to study the culture any more than you had to be English to appreciate Shakespeare.

  However much African Americans know about the general conditions of their ancestry, Gates found—as Rick Kittles had done, and as I had done on a much smaller scale—that they can sometimes be shocked when they first hear that so much of their DNA is rooted in Europe. We have already seen the sequence of reactions from initial surprise or even anger to eventual acceptance among the customers of African Ancestry. But there are some African Americans who are sure that absolutely all their ancestors are from Africa. Probably the most famous of these is Oprah Winfrey. She is also numbered among Dr. Gates’s friends and was one of the guests on the first series of African American Lives and the subject of his book Finding Oprah’s Roots. For this she took a mitochondrial DNA test the day before she was due to leave for South Africa to visit the orphanage that she was sponsoring. As soon as she arrived in South Africa, she made her famous quote “I am a Zulu”, which was flashed around the world, much to Gates’s surprise. As the golden rule of DNA television is to keep the results a secret until the on-camera “reveal,” he
immediately rang the lab to ask if they had given the results to Oprah. They answered that they certainly had not, and, in any event, as the DNA sample had only just arrived, it would be several days before they had the results. When the lab results did come back, it was obvious that Oprah’s mitochondrial DNA matched others from West Africa, in particular Liberia, much more closely than anyone from Zululand. That was always the more likely origin. Zululand, which is situated in South Africa far from the coast, is a long way from the main centers of slavery. Showing a certain amount of surprise but certainly not indignation at having her roots moved halfway across the continent, Oprah quickly and graciously assimilated the new information. She may not have been a Zulu, but she was certainly African, a point reinforced when an AIMs test found no trace of European DNA. A remarkable woman in more ways than one.

  At this point I slipped my own DNA into the conversation. From a genetic point of view, I was part African myself. My own chromosome portrait had revealed that a DNA segment at the end of the short arm of my chromosome 11 was half European and half African. “If I were an American, would I qualify as an African American?” I inquired. Bobo, who laughs even more zestily than Gates, said that the infamous “one-drop” rule would almost certainly have classified me as a slave in the old days. The short arm of chromosome 11 is packed with important genes, one of which controls insulin production. Thus one of my two copies of the insulin gene is African, and since the only place insulin is made in the body is inside the pancreas, I considered myself, metaphorically at least, to have a black pancreas.

  As the evening progressed, we meandered through a wide range of topics: The situation in Brazil, where there are an astonishing 134 unofficial racial categories. The case of P.B.S. Pinchback, the first black acting governor of any state, Louisiana, who was sworn in during 1872 and who, although the son of a slave, appeared very white indeed. “You would look like Michael Jordan next to him,” quipped Gates. The sad case of the writer and critic Anatole Broyard, whose daughter Bliss wrote the touching biography One Drop. Broyard was diagnosed with prostate cancer and, because of his appearance, treated as a white man. Had his doctors been aware of his true ancestry, which was partly black, they may have treated his cancer more aggressively and in so doing perhaps saved his life.

  As the party eventually broke up, I felt so very fortunate that my profession had brought me into contact with such wonderful company. The long reach of genetics, far beyond the confines of the laboratory bench, had led me all over America and the world. Neither at supper that night, nor in any of the revealing conversations that I had been privileged to have with African Americans during my journey, had we gotten anywhere near “solving” the relationship between genetics and race. There is no “solution.” But knowing that at least one of my ancestors had been black, and that my own pancreas depended on that legacy, had certainly blurred the edges of my perception and, not for the first time, brought home to me the myriad threads that bind us all into the same human family.

  THIRD MOVEMENT

  19

  The Private View

  Welcome to the chromosome portrait gallery.

  Scientific papers traditionally end with a “Discussion” section, and the temptation here is to follow that convention and write a final chapter that summarizes the rest of the book and comes up with ponderous conclusions. But that is not how road movies end, is it? Most of the time the protagonists never get to their destination and end up, like Peter Fonda and Dennis Hopper in Easy Rider, blasted by a shotgun and dead at the side of the road. Even if I was feeling the worse for wear at the end of three months on the move, my chest was only wheezy, not full of lead shot.

  I did return with Ulla to the United States six months later, carrying with me an armful of chromosome portraits and ready to go through them with my volunteers. Time and money confined the face-to-face meetings to the east coast, so I sent individual chromosome portraits to everyone else by snail- or e-mail, and followed up with a phone call. I had asked the volunteers to make a stab at what they thought their own portrait might look like before I showed it to them, and then observed how they reacted when the canvas was revealed. The journalist in me was waiting for a series of dramatic outbursts when expectations met reality, but there were none. Most of the time my volunteers either declined to hazard a guess or, when they did, found that it more or less matched what their portraits revealed. When it did not, the reactions were muted and reflective rather than indignant. But what do the portraits look like? I will let them speak for themselves.

  Welcome to the “Private View.” Take a glass of champagne in one hand and a canapé in the other. Think of this last chapter as the catalog. Go to the color insert section and take your time to browse.

  The first portrait in the gallery is of my New England volunteer “Margo Channing.” She is, as you see, all one color: blue. This means that without a single exception, all of “Margo”’s DNA has a European origin. It is not the most colorful portrait or, you might think, the best to choose to begin our tour of the gallery. More Rothko than Magritte. But, despite its uniformity, this portrait is one of the most interesting and surprising of all. I could equally well have shown you the portraits of my other New England volunteers: “Terry Malloy,” “Rio McDonald,” “Anna Christie,” “Lisa Fremont,” or “Rose Sayer.”* All of them are exactly the same, solidly blue throughout without a trace of DNA from either African or Native American ancestors. Remember that all my sitters in this part of the gallery are descended from European settlers who arrived in New England during the seventeenth century, many of them before 1650. And yet there is not the slightest echo of any interbreeding with Native Americans, with whom they lived in close proximity. Had there been, then the blue chromosomes would have been flecked with orange. That was what I had been expecting, having seen the effects of European settlement among other indigenous people where genes are quick to cross ethnic boundaries in both directions. But in New England there is no sign of it.

  I can only conclude that, if there had been any intermixing between early New Englanders and the indigenous tribes living around Plymouth and Cape Cod, the offspring would have stayed within the Indian tribes rather than being absorbed into the English settlements. The single exception is “Atticus Finch.” His portrait shows a tiny fleck of orange at the end of chromosome 9.

  “Atticus,” if you recall, had reason to believe he was descended on his father’s side from Ots-Toch, the daughter of a Mohawk mother and a French father. Although I cannot prove it beyond any doubt, I think it likely that the speck of orange in “Atticus”’s chromosome portrait really is the genetic legacy that he inherited directly from Ots-Toch and her Mohawk mother. The fact that the portraits of my other New England volunteers were all uniformly European blue throughout makes me think that the little bit of orange in “Atticus Finch”’s portrait is genuinely from his Mohawk ancestor. After twelve generations of doubling dilution, there was never going to be much left of her DNA in “Atticus”’s genome, and the single speck we see in his portrait is about all I would have expected.

  One of the attractions that drew me to the chromosome portraits, as well as their visual impact, is that it is easy to look up which genes correspond to which particular chromosome segments. The Human Genome Project located all our genes at fixed points along the chromosomes, so it is a simple task in “Atticus Finch”’s case to identify which genes have come down to him from Ots-Toch. This will identify the parts of “Atticus”’s body that are running on Mohawk DNA. Among several genes that chromosome 9 carries with frankly obscure functions, there is one that is familiar to all of us. This is the gene that controls our blood group, deciding whether we are group A, B, AB or O. We all have two copies of this gene, one from each parent, and in “Atticus”’s case one of them has been inherited from Ots-Toch, while the other has come from a European ancestor on his mother’s side of the family. Both Mohawk and European genes are working together to decide “Atticus”’s blood group,
and since he is fit and well, it looks as though they are doing a good job.

  “Harry Lime,” a staff member at the New England Historic Genealogy Society who also volunteered to have his chromosomes painted, was the only other European New Englander to have anything other than a uniformly blue chromosome portrait. In his case, as you can see, the speck of color was not orange but green. “Harry Lime” therefore has an African ancestor. When I unveiled the portrait, his first question—to himself more than to me—was to wonder who this ancestor might have been. Being a professional genealogist, he set off in search of this unexpected family member. Like “Atticus Finch”’s portrait, this was only a splash of color amid a sea of blue, suggesting that, whoever it was, his African ancestor had lived a very long time ago. The likelihood is that he or she was an African American, but even that is not certain. Some Europeans, myself included, have small segments of African DNA that must have entered the British gene pool at some time in the past. The last time I spoke to “Harry,” he was still on the track of his elusive African ancestor.

  As we did with “Atticus Finch,” we can also see which of “Harry”’s genes are firing on African DNA. The section of chromosome 7 containing African DNA does not hold any well-known genes. However, there is one intriguing gene among the otherwise uninspiring collection. It belongs to the family of genes that control the exquisitely sensitive receptors that give us our sense of smell. It is a large family dispersed around the human genome, with each member of the family capable of sensing particular odors. In “Harry”’s case one of these is being run by a collaboration of DNA from one African and one European ancestor.

 

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