By Ricardo G?ndara
Sunday, October 08, 2006
Carla Nickerson knew she had a thing about Ghana. For the past eight years, she has traveled to the African country ? including on her honeymoon ? because she felt drawn there. With each succeeding visit, she felt more and more of a blood connection.
On one of her trips, she toured a castle in Cape Coast, where African Americans were imprisoned while awaiting transport during the transatlantic slave trade that spanned the 16th to 19th centuries.
"I was in the men's quarters, a dark, stone room about 60 by 80 feet with tiny windows. It seemed that I heard and smelled things. I had a meltdown. I really felt that a male ancestor had been there," Nickerson recalls.
Now, she's sure some of her ancestors are, indeed, Ghanaians. According to the results of a home DNA test, her father, Leon Nickerson, shares "paternal genetic ancestry" with the Ewe and Akan peoples of Ghana. DNA is the material in our cells that contains the genetic information passed down from parents to children.
On her mother Verdell's side, she shares ancestry with the Tikar people of Cameroon, another African country. At least, that's what it says on the "certificate of ancestry" from African Ancestry Inc., a Washington, D.C.-based company that specializes in helping African Americans learn whether their DNA matches that of present-day people living in Africa.
DNA testing is the latest tool taken up by Americans seeking an answer to the universal question: Who am I? The technology is being used to fill the gaps left by searches of genealogical records (births, deaths, marriages and the like). It's especially useful for African Americans, whose past is often difficult to trace because of the upheavals of slavery, and for adoptees with little knowledge of their birth families.
DNA home tests, which became available in 2000, cost as little as $100 and as much as $1,000 for more extensive analysis. But detractors say that the results might not be all that useful in pinpointing geographic origin. Comparing your DNA with that of people somewhere else in the world today only reveals whether your genetic sequences (called markers) match up ? not where those people (and hence, your long-ago relatives) originally came from.
Nickerson doesn't care. She knows at least part of her past.
"When I opened the envelope and saw our DNA matched the Ewe and Akan peoples, I said, 'I know those people. I know that culture,' " she says. An actor and an artist, she has decorated her home off East 12th Street with musical instruments, masks, sculptures and other artwork from Ghana.
Nickerson is one of more than 7,000 customers ? 95 percent of them African Americans ? who've used African Ancestry to test their DNA. Clients' samples are compared with a database of 25,000 DNA samples from 400 indigenous African groups collected over the past 12 years, mostly from west and central Africa, says Gina Paige, president and co-founder of the company. She says African Ancestry tested 1,000 people in 2003, its first year, and three times that many in 2005.
"They take the tests because they know little about their family history," says Deborah Bolnick, a geneticist and lecturer in the department of anthropology at the University of Texas. "With the DNA test, they get a certificate telling them what populations in the world contain people with identical DNA sequences. That's at least a start for them."
African Ancestry sends DNA samples, which are collected from mouth swabs included in its home test kits, to Sorenson Genomics LLC, a laboratory in Utah where scientists extract and sequence the DNA. Each sample is compared with its database of African DNA samples. If an African match is found, customers get a certificate saying they share genetic ancestry with groups of people in specific areas of Africa; if there is no African match, the certificate states which other population group shares ancestry with the sample. Customers get results in about six weeks.
Several other companies offer the same testing to help people establish blood lines. Family Tree DNA of Houston was the first American company to offer the service and has tested 70,000 people since 2000, says company president Bennett Greenspan. The company also tests for Native American and Jewish ancestry. People can even test for ties to Genghis Khan, the notorious ruler and founder of the Mongol Empire, whose sons spread their Y chromosomes across Central Asia. To date, no Western European or North American male has matched the DNA profile of Khan, according to Family Tree DNA's Web site.
"DNA testing helps you get to your roots faster. It won't hand you your family tree," says Megan Smolenyak, genealogist and co-author of the book "Trace Your Roots With DNA: Using Genetic Tests to Explore Your Family Tree." She adds, "It's a matchmaking game, matching DNA with other people."
African Ancestry also got a boost earlier this year when it was used in the PBS documentary "African American Lives" to test prominent people such as host Henry Louis Gates, Jr., chairman of African and African-American Studies at Harvard University, and Oprah Winfrey. In July, Gates was inducted into the predominantly white Sons of the American Revolution after testing revealed that one of his ancestors was a free mulatto who fought in the Revolutionary War.
The popular use of DNA testing coincides with a growing database of DNA samples worldwide. The National Geographic Society started The Genographic Project, a five-year research effort to collect DNA samples from throughout the world, to determine where people originated and how people got to where they are today. For $100, anyone can participate in the project by getting a cheek swab home test to determine mitochondrial DNA (passed down from mother to child, revealing maternal ancestry) or the Y chromosome test (passed down the male line from father to son).
The information revealed by the tests attracts genealogy buffs such as Nickerson, Joe Hood and Leo Little, all of Austin. Hood and Little have spent years researching their families and have traced their relatives through historical records. Tests from Family Tree DNA of Houston, however, helped them dig deeper in their families' histories by identifying distant relatives whose DNA matches theirs.
Little, a retired electrical engineer, has been researching his family since 1960. When he posted a message on a www.ancestry.com
bulletin board, a Dallas man with the same last name responded. Leo Little convinced him to take a DNA test; they matched on 36 of the 37 markers.
Family Tree DNA gives people the option of releasing contact information to others who are a similar DNA match; through the company, the Littles learned of 80 others sharing the same last name from throughout the U.S., Canada, Great Britain, Scotland and Northern Ireland. Among the various Littles was a group from North Carolina and Tennessee.
"We pooled all of our research," says Leo Little. "It was like pieces of a puzzle. As it turns out, we descended from Abraham Little, who lived in Virginia in 1705. It was very exciting."
Hood assumed his mother's role as chief family researcher and learned through records and DNA testing that he descended from Enoch Hood, born in 1784 in Virginia. Hood made the connection when he found a man named Clyde Hood of Missouri through online research. Their DNA matched on 36 of 37 markers.
In his research, Hood also learned of another relative (he refused to name him to protect his privacy), whose great-great-great-great-grandmother lived next to Enoch Hood. Hood believes Enoch Hood, who was married, had a child with his neighbor. "I have the odd status of having a picture of this woman who was my third great-grandfather's girlfriend. We also know she lived to be 104," Joe Hood says.
DNA not an identity
How reliable are DNA tests in answering the "Who am I?" question? The answer depends on who's talking. Nickerson, for one, has few doubts.
Bolnick, the geneticist at UT, has her doubts. She believes that DNA patterns that exist in the world today might not be reliable when it comes to figuring out an individual's ancient origins.
"DNA tests can tell you where some of your relatives live today but not where they lived thousands of years ago. People moved a lot," Bolnick says. Not only that, she says comparing DNA to present-day people belonging to certain ethnic groups can be misleading.
"The problem with that is that there is no clear-cut connection between DNA and ethnicity. With these tests, you may identify groups that some close relatives belong to today, but you may also be closely related to people in other groups, or in other parts of the world that you may not know about because their DNA samples have not yet been studied," Bolnick says. "I just think that some conclusions are premature."
Paige of African Ancestry says consumers are told only whether they share a connection with present-day people living in Africa. "We are clear. We can't tell them ancestry of every lineage. But, for people who know nothing, knowing one lineage is very important information," she says.
Another caveat to DNA testing: People might not like what they find. Thirty percent of those tested by African Ancestry to determine their African lineage prove to have European ancestry on their paternal side, says Paige. (Historians have long contended that white slave owners impregnated large numbers of black slaves.) However, nearly all maternal tests done by blacks find African roots.
Bolnick agrees that DNA can reveal valuable information in many cases. "When people are researching surnames, DNA tests can be useful because they can either confirm or not prove if they're related to someone. For African Americans and others, like adoptees, who may know nothing about their distant ancestors, the tests can tell them where some of their relatives live around the world," she says.
Nickerson is satisfied with her findings: "I feel very confident in the way African Ancestry does its cataloging and sampling. I believe in my heart the results are true."
Besides, in Ghana she sees people who look like her. "It just feels right," she says.
How to test your DNA
Visit the Web site of any DNA testing company, such as Family Tree DNA in Houston (www.familytreedna.com
), to read about the different types of tests, check prices and buy a mail-order testing kit. If you call Family Tree DNA, (713) 868-1438, a representative will help you choose the right test.
?The test will arrive through the mail, with instructions in several languages. Family Tree DNA's prices range from the $149 for the Y-Chromosome (paternal lineage) 12-marker test to $995 for the Super DNA test that includes both paternal and maternal lineage.
?Kit contains three cotton swabs and three collection tubes. Scrape the inside of your cheek with the swab and deposit the 'cheek cells' into the tubes.
?If you sign a release form, you give the company consent to share your name and e-mail address with others who have a similar genetic fingerprint.
?Mail the samples in an envelope provided. You will receive results in four to six weeks
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