Oct. 21, 2005 -- To help African-Americans trace their ancestry, companies are selling DNA-based genealogy tests that claim to pinpoint where a client's ancestors came from in Africa. Several celebrities have taken the tests, including talk show host Oprah Winfrey, director Spike Lee, actor Isaiah Washington and now ABC News' Ron Claiborne.
"Like so many Americans, I have always wondered about my own roots," Claiborne said. "But as with many African-Americans, I have never known from where in Africa my ancestors came. For most of us, the search ends here, in slavery."
Twenty million people were taken from Africa in chains, with no records of who they were or where they came from.
"The transatlantic slave trade broke apart families, cultures, traditions," said Rick Kittles of African Ancestry, www.africanancestry.com, which offers the DNA test. "Many African-Americans, especially young African-Americans, they think their history started with slavery."
When the miniseries "Roots" aired 28 years ago, many black Americans were inspired to search for their own roots. At the time there was little they could do. But today, DNA testing has allowed more than 100,000 Americans to trace their genealogical ancestry back to Africa.
About 3,000 people have been tested at African Ancestry, according to the company. The tests cost between $130 to $650, and in a sign of the growing popularity of the testing, African Ancestry doubled its revenue between 2003 and 2004.
"There are thousands of different ethnic groups and communities and different languages spoken in Africa," Kittles said. "But the communities that we have sampled are those that the historians have suggested have played a big role in terms of the transatlantic slave trade."
As a surprise, Keelechi Igwin, from Nigeria, submitted samples of his wife's family's DNA for testing. His wife, Nia, is from Maryland.
"The thing about being married to Keelechi is, he and his family have the fortune to be able to trace back where there family started from," Nia Igwin said. "Black people living in America, unfortunately, we don't have that. That was taken from us."
The results show Nia Igwin's ancestors are from present-day Cameroon and Nigeria, including Ibo, just like her husband.
"Now it's something to help make things a lot more clear for us, and that's a jewel to me," Nia Igwin said.
Critics say African Ancestry's database is much too small for its results to be so specific. The company said it has a database of more than 22,000 DNA samples from nearly 400 indigenous African groups and reports a match if the statistical probability is 90 percent or higher.
"It is not possible to link anybody in this hemisphere to any ethnic group in Africa at this time," said Bruce Jackson, a geneticist at the University of Massachusetts at Lowell.
Even knowing the possible limitations, Claiborne decided to submit his DNA for testing.
The results were revealed on today's "Good Morning America:" Claiborne's maternal lineage is from Ghana.
"It's like a door has been opened," Claiborne said. "All my life I've thought about how I'd never know, that there would never be a way to figure out where my family came from."