"We now know that our ancestors brought something with them that not even the slave trade could take away: their own distinctive strands of DNA. And because their DNA has been passed down to us - their direct descendants - it just might be the key that unlocks our African past." - Henry Louis Gates, head of the Department of African and African American Studies at Harvard University
Last night's concluding part of "African American Lives" on PBS was fascinating, as it answers a key question: "Where do I come from?" They had researchers from African Ancestry (who I mentioned yesterday), University of Maryland, Pennsylvania State University, and Cambridge University do the DNA tests of genetic strands. There were three tests: an admixture test to give an overview of how African, European, Asian, etc. folks were (Mark Shriver, a white population geneticist at Penn State, talked about how surprised he had been by his own test - which had come back 86% European, 11% sub-Saharan African, and 3% Native American - and how his mother wanted him to stop publicizing these results). Then to test for specific African ancestry, two more tests were done: a mitochondrial DNA test that traces the matrilineal line (mother to grandmother to great-grandmother, and so forth). The Y chromosome test is only done on males - women must get a male relative to do it - and traces the patrilineal line. The conclusions for some of the more famous case studies:
Oprah Winfrey:
The billionaire talk show host said that she didn't believe that she had any European or Native American ancestors. Her admixture test showed her ancestry to be 89% sub-Saharan African, 8% Native American, 3% East Asian (researchers said that Native American ancestral traces show up here too), and 0% European. Henry Louis Gates told Oprah that, no, her other test results didn't show Zulu ancestry, as she has claimed (and she had to take a breather). She descends from the Kpelle people (who cluster in the Guinea Highlands of what is now central Liberia and Guinea), the Bamileke people (who cluster in modern-day Cameroon), and a Bantu tribe in Zambia. I hope Oprah travels there, and does a show about these findings. Let us not forget that in the previous installment, Ms. Winfrey - born to unwed parents in rural Mississippi - discovered that an ancestor owned land after the Civil War, and had a school for black children on it (and she broke into tears upon hearing the news).
Quincy Jones:
Mr. Jones' admixture test showed his ancestry to be 66% sub-Saharan African, 34% European, and 0% Native American. Given family stories, the music producer was surprised that he had no Native American ancestors, and shocked at the high percentage of European ancestry (the average for black Americans is 20%). His Y chromosome test - which traces the patrilineal line - showed only European lineage and no African match (not unusual as apparently 3 out of 10 Y chromosome tests for black Americans reveal European ancestry). His mitochondrial test - which traces the matrilineal line - connected him to the Tikar tribe, who cluster in present-day Cameroon. And apparently the Tikar people are famous for their music and artistic genius, hence no surprise given Jones' prowess in the music industry.
T.D. Jakes:
The famous minister's Y chromosome test showed him to be of Igbo descent (clustered in what is now Nigeria). He was the only one of the nine famous guinea pigs to correctly guess his African ancestry.
Whoopi Goldberg:
Her admixture test revealed her ancestry to be 92% sub-Saharan African, 8% European, and 0% Native American (which meant that family stories about having such ancestry were untrue). The comic / actress descends from the Papel and Bayote tribes, who mainly cluster in modern-day Guinea-Bissau. Apparently, these were popular tribes in the slave trade.
Mae Jemison:
The first black female astronaut to go into space (who is light-skinned) had no discernible European ancestry in her admixture test. Out of all the famous guinea pigs, I expected her test to come back with the most mixed ancestry. Not. Her ancestry reveals her to be 84% sub-Saharan African descent, 13% East Asian, and 3% Native American. Researchers were unable to find a conclusive match for her in terms of a specific African tribe. Researchers explained her high East Asian ancestry (for black Americans) to the fact that Chinese laborers were sent to Mississippi - her family's ancestral state - in the late 1800s, so apparently one of her great-grandfathers may have been such a laborer. She was surprised to be of Asian descent (I wasn't...has she looked at her eyes?), although she indicated that people had told her such during her travels to Asia. She figured that it was just traces of Native American ancestry.
Chris Tucker: The comic's admixture test came back 83% sub-Saharan African, 10% Native American, and 7% European. He guessed that he was descended from a tribe in modern-day Ghana. His Y chromosome test was the most intriguing of the group: it linked him to the Mbundu tribe, who inhabit modern-day central Angola. In fact, the DNA link was so strong that researchers said it was within the last eight generations...which is rare (researchers were only able to trace his family tree to the 1830s, and you may recall how one of his fascinating relatives kept selling plots of land to keep it in black hands during the Jim Crow Era). Apparently 1 in 4 U.S. slaves came from what is now the Congo-Angola region. Mr. Gates accompanied Mr. Tucker on a trip to Angola, where they visited a village in the region where the Mbundu people cluster (and folks were very excited to see him, did a homecoming celebration for him, and a village elder / griot talked about how they had heard stories about people disappearing during the slave trade).
Henry Louis Gates:
The head of Harvard University's African And African-American Studies department had an interesting family history. Researchers traced his family tree back to the American Revolution (where a relative fought). His admixture test revealed his ancestry to be 50% sub-Saharan African, 50% European, and 0% Native American. Like Quincy Jones, his Y chromosome test revealed only European ancestry (in common with British and Dutch males). His mitochondrial DNA test also revealed European ancestry (in common with French and Irish) - and it is very rare for black Americans to reveal European blood on the woman's (mitochondrial) side, so there is definitely a creepin' story there - with weak traces of ancestry from modern-day Egypt. No sub-Saharan ancestry. To help trace his sub-Saharan African ancestry, researchers took his 50% DNA strand that was African and compared it to African individuals. The result came closest (but not definitely) to the Mende people, who cluster mostly in modern-day Sierra Leone, as well as Liberia. _________________ La vie est un privilege, elle ne vous doit rien!
Vous lui devez tout, en l'occurence votre vie
Inscrit le: 01 Mai 2006 Messages: 107 Localisation: Paris
Posté le: Mer 26 Juil 2006 20:42 Sujet du message:
DNA identifies African roots for Black Americans
By Emily Crawford
Jacqueline Pitts, a 51-year-old African-American with a passion for genealogy, could never trace her family roots beyond the 1800s because the institution of slavery had scattered and sold her ancestors, leaving no written records behind. Then she heard about African Ancestry, a company in Washington that offers DNA testing to establish African roots for black Americans.
Pitts, who lives in Queens, N.Y., sent in a sample of her DNA, and six weeks later she had the results: Her DNA matched up with that of the Bamileke people of Cameroon in West Africa. The Bamilekes are one of the farming tribes in what is called the Grasslands of western Cameroon. They raise livestock and grow maize, yams and peanuts.
It was a spiritual moment for Pitts, a retired deputy assistant prison warden who had studied African history for years and could easily recite the names of many of the tribes. "It took me 51 years to say the name Bamileke," she said. "I've said many other groups' names but never until that day did I say the word Bamileke, and I felt like my ancestors knew that I was saying that name. And they were like, 'She knows who we are.'"
For several years, DNA evidence has been used to confirm identity in criminal matters, but increasingly, commercial genealogists and genetic researchers are using it to bridge centuries in family trees, giving some people their first glimpse at a past previously unknown. Some companies, such as Trace Genetics, specialize in determining Native American ancestry. Others, like Family Tree DNA, offer to pinpoint where a customer's ancestors originated, whether, for instance, they came from Ireland, Scandinavia or Poland.
For blacks, whose ancestors arrived in this country on slave ships, DNA offers a specifically valuable tool.
"As a person of color, there is only so much you can do with government records," said Gina Paige, president and cofounder of African Ancestry. "During slavery, Africans were not recorded as people, with last names and dates of births; they were recorded as property. This technology takes people's family research to the next level."
African Ancestry, which is wholly owned by black investors, has helped some 1,200 people since its inception in February 2003. "The bridge to the past collapsed with the advent of the slave trade," said Dr. Rick Kittles, cofounder of the company and also director of molecular genetics at the National Human Genome Center at Howard University. "Tracing ancestry through DNA can lend us some insight about our potential ancestors and potential places of ancestry. For untold numbers of people, knowing that is better than knowing nothing."
Kittles has spent 10 years collecting DNA samples from individuals in West and Central Africa and has compiled them in a database together with samples taken from other ethnic groups across the continent. All told, the company has over 21,000 African lineages and 95 ethnic groups registered in its African lineage database, the largest of its kind in the world.
Customers can choose to look backward through the lineages established through either their mother or their father. The company provides what it calls the PatriClan Test Kit, which uses the Y-chromosome (carried only in males) to compare the customer's DNA sample with its database. The MatriClan tests mitochondrial DNA, or mtDNA, which is inherited exclusively from the mother. The DNA goes back over hundreds of generations.
Some 70 percent of those who use the PatriClan test can expect to find database matches with a present day country in Africa, Paige said. For those who use the MatriClan test, 95 percent receive a match that reveals an African ancestry link. The test can also identify a specific ethnic group, like the Hausa of Nigeria or, as in Pitts's case, the Bamileke of Cameroon.
Sometimes the search comes up with surprises. Gabriel Tolliver, a black 38-year-old TV and film producer who now lives in Brooklyn, learned that his paternal ancestors came from Germany. Finding a European ancestor happens occasionally for black clients using the paternal tests. This is because slave owners frequently had sex with their female slaves, Paige said, adding their Caucasian genes to the line of succession.
In Tolliver's case, it was his older brother who had spearheaded the family genealogy project, which allowed Tolliver to discover that on his father's side he had a great-great-great-grandmother who was of Irish descent. She had married a man who was half black and half Cherokee, a liaison that was certainly unusual for the times, he said. The testing "put another piece of the puzzle into play," said Tolliver, who also traced three lines on his mother's side to the Mende and Temne people in Sierra Leone and the Kru in Liberia.
The DNA search is especially helpful for people who are adopted and who wish to find clues to the identity of their biological parents. Recently, African Ancestry tested an adopted, biracial teenage boy whose parents knew his biological mother was Caucasian, but not what his father was. The test traced the boy's paternal ancestors to the Ibo people of Nigeria. His father wrote to the company thanking them for the search and said it had greatly pleased his son to find out where he had come from.
The service has also galvanized some clients to make plans for a trip to Africa. After receiving her results, Pitts searched for Bamileke immigrants in New York. Eventually she met with Martin Chungong Ayafor, the ambassador of the Cameroon mission in New York, who is also a Bamileke. Pitts has also made contact with a Bamileke citizen in Brooklyn, a librarian, who she hopes will serve as her liaison when she journeys to Cameroon.
The DNA testing allows blacks to trace their lineage back to a specific place rather than losing it inside a giant continent. "Now I can identify with Cameroon rather than saying I came from Africa," Pitts said. "As a human being, it is just natural to want to know where you came from."
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