DNA rewrites history for African-Americans
By Richard Willing, USA TODAY
At age 4, Mika Stump was abandoned by her birth mother in New York City's Penn Station. Brought up in a foster home, she knew nothing of her African-American roots, she says, other than, "I was black."
Melvin Collier, a graduate student at Clark Atlanta University, learned his DNA matched the profile of the Mbundu people of Angola.
By Michael A. Schwarz, USA TODAY
But a DNA test she took recently showed strong similarities between Stump's genetic code and the Mende and Temne people of Sierra Leone, in Africa.
Now, "I have a place where I can go back and say, 'This is who I am; this is my home,' " says Stump, 34, a homemaker and mother of six in Basalt, Colo. "That's something I never, ever expected to say."
As the descendants of slaves, black Americans have long faced huge obstacles to researching their family histories.
However, advances in the use of DNA — the cellular acid that determines physical characteristics and is inherited from one's parents — are allowing African-Americans to connect with previously unknown ancestors. (Related item: Genetic genealogy's price tag)
Some are using DNA to test the oral traditions that African-American families have relied on to transmit their histories. And in a 21st-century update of Alex Haley's 1976 novel Roots, others are seeking to match their DNA to the ethnic groups in Africa to which their ancestors might have belonged.
For black Americans, however, there are some drawbacks. DNA evidence has confirmed some family stories but debunked many others. For example, most of the nine black celebrities who underwent genetic testing for the PBS documentary African American Lives believed they were part Native American.
One of those tested, Oprah Winfrey, 52, says on the program that to many African-Americans in her generation, being "a little Indian" was desirable. The two-part documentary, which began running this week, says genetic testing revealed that only two of the nine celebrities tested — Winfrey and comedian-actor Chris Tucker — likely had Native American ancestors.
The new wave of genealogical testing also has reopened one of America's ugliest wounds by confirming with science what historians have contended for generations: In slavery times and beyond, large numbers of black women were impregnated by white slave owners or other white men in positions of power.
About 30% of black Americans who take DNA tests to determine their African lineage prove to be descended from Europeans on their father's side, says Rick Kittles, scientific director of African Ancestry, a Washington, D.C., company that began offering the tests in 2003. Almost all black Americans whom Kittles has tested descended from African women, he says.
That's partly why genetic genealogy is "not for the faint-hearted," says Melvyn Gillette, a member of the African American Genealogical Society of Northern California and a longtime family researcher.
"Before you go opening any door, you need to ask, 'Am I really ready for what might be behind it?' " Gillette says. "Not everyone is."
Tracing patterns, finding links
Each person's DNA is unique, but some DNA patterns remain relatively unchanged within families as well as within ethnic and geographical groups. Genetic genealogy tracks those types of DNA.
One test examines markers of DNA on the Y chromosome, which passes virtually unchanged from fathers to sons. Another test uses mitochondrial DNA, which children of both sexes get from their mothers.
Such tests allow DNA researchers to go back in time to confirm paternal and maternal lines, or to debunk them. By tracing tiny DNA mutations, researchers can link a living donor to a group in Africa that shares those DNA patterns.
A separate test analyzes inherited mutations to estimate an individual's ethnic makeup: European, African, East Asian, Native American or a combination.
Genetic genealogy has been pushed forward by a "significant increase" in data that can be searched online, says Scott Woodward, director of the Sorenson Molecular Genealogy Foundation in Salt Lake City. That enables test-takers to compare results with people descended from the same families or ethnic groups.
The tests, available through about a dozen commercial labs and non-profit groups, are increasingly popular. Kittles, who is of African ancestry, says his company has sold more than 4,000 tests at $349 apiece since it opened in 2003.
Bruce Jackson, a geneticist at the University of Massachusetts Lowell, says the African-American DNA Roots Project he co-founded in 2001 has been "swamped" by African-Americans who have volunteered samples to aid historical research. Afrigeneas, a website on black American genealogy, recently added a discussion forum on DNA research, webmaster Valencia King Nelson says.
The tests that seek to match the DNA of a living black person to samples from African groups have touched a chord with African-Americans who had thought they would never know much about their distant forebears.
"You sit with (white) folks who say, 'My family goes back to County Cork, (Ireland)' or, 'My family goes back to Sicily,' " actress Whoopi Goldberg says in African American Lives. "And you say, 'Umm, I don't know, I think Florida.' "
Testing commissioned by the program found that Goldberg was related to the Pepel and Bayote people, who live near the Atlantic Coast in Guinea-Bissau.
Anita Wills of Oakland used DNA testing to confirm an old family story — and to discover dozens of relatives on both sides of the Atlantic Ocean.
Wills searched her paternal DNA against one of the increasing number of databases maintained by genealogy organizations and hobbyist groups. She confirmed what she had long believed: Her ancestors included a white planter in 18th-century Virginia. She also found "DNA cousins" — families with the same genetic pattern — in England, Ireland, Wales and Russia.
"I knew our family's history was complex, but I really had no idea," Wills says. "DNA showed me."
Melvin Collier, a graduate student at Clark Atlanta University, suspected from his family's oral history that a great-grandfather on his father's side had been a white slave owner. So he had DNA from his mother's side of the family tested instead. Collier was delighted to learn that it matched the profile of the Mbundu people of Angola.
Collier knew a Mbundu who lived in Atlanta and who invited him to an Angolan celebration. There, Collier says, he was encouraged to get up and dance "for the family." Collier says he's "not much of a dancer," and was unfamiliar with Angolan music, but he says he obliged, to loud applause.
In Catonsville, Md., DNA tests helped Angela Walton-Raji confirm stories of a Native American ancestor that she had been told as a child.
"I knew it was true in my heart," says Walton-Raji, who researched her ancestry through paper records for 20 years. But "with DNA, there's no denying it."
Surprises and disappointments
Test results can be surprising to whites as well. Mark Shriver, a white geneticist at Penn State University who helped develop the test that detects multiple ethnic backgrounds, learned his background was about 11% West African.
"People have multiple ancestries," Shriver says. "I don't have to just say that. I'm proof."
PBS
Harvard professor Henry Louis "Skip" Gates Jr. concluded from tests that he's 50% white.
Using DNA to pursue ancestry has not been a positive experience for every black American who has tried it. In Oakland, a member of Melvyn Gillette's amateur genealogical group was crushed to learn that her line of male ancestors traced back to a white Italian, and not a black resident of Madagascar as she had expected.
"She couldn't get past it," Gillette says. "She ordered more tests."
At African Ancestry, an unhappy customer peppered company President Gina Paige with e-mails after DNA testing of his male line indicated that he had descended from a white man. "He was especially upset that (the ancestor) was German," she recalls. "More so than white, he had a problem with being even a little bit German."
Kittles, the company's scientific director, says new customers now are counseled about the potential impact of unwanted results. African Ancestry's application form permits customers whose male line DNA does not match any known African groups to forgo further testing.
Most of those customers, Kittles says, ask the company to go forward and to tell them whether it finds a match to a non-African lineage.
For African-Americans accustomed to tracing family histories through conventional means, DNA can upset long-held conclusions.
Henry Louis "Skip" Gates Jr., host of the PBS documentary and chairman of African and African-American studies at Harvard University, used court documents, family records and slave rental agreements to trace his family back to Maryland in the mid-1700s.
To test his family's oral history — that it was descended from a freed slave and her former owner — Gates found the former slave owner's white descendants in Maryland and California. Their paternal line DNA was compared with Gates'.
If all three had descended from the same man, the DNA sequences on their Y chromosomes should have matched.
They didn't. The white slave owner was not Gates' great-great grandfather after all. Gates was shocked.
Then, a follow-up test on DNA from his mother's side carried more unexpected news. The Harvard professor had a white maternal ancestor, too. Gates concluded that he is probably 50% white.
"I'll never see my family tree in quite the same way," Gates says on the PBS program. "I have the blues. Can I still have the blues?"
Genetic genealogy has begun to attract critics. Jackson, the geneticist and co-founder of the DNA Roots Project, says claims that DNA sequences can be traced to specific African groups are "cruelly misleading."
"Nigeria alone has 261 recognized ethnic groups," he says. "You'd have to test them all, and then you'd only be at the beginning."
However, Peter Forster, a geneticist at the University of Cambridge in England, says public and private databases that date to 1981 now contain more than 35,000 samples of DNA, more than enough in most cases to provide accurate "geographical and tribal information."
Terry Melton, president of Mitotyping Technologies in State College, Pa., and a specialist in mitochondrial DNA, worries that tests that focus only on DNA from a mother or father's line can give a distorted view of a family's history.
"You can be 31/32 black, but if that 32nd ancestor is white you could show up as white, too," she says. "That can be very confusing."
For amateur genealogists such as Joe Madison, the value of DNA-based research far outweighs any of its shortcomings.
"The connection to the homeland was deliberately broken by slavery," says Madison, who has discussed genetic genealogy on the black-oriented talk show he hosts on XM Satellite Radio.
"Now, after all this time, that chain has been soldered together by science," Madison says. "Being part from Sierra Leone, part from Mozambique, that's something I can pass on to my children. And that's what it's all about."
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