Historical DNA Reveals Connection Between Living People And Enslaved African Americans

We don’t know their names, but a new historical DNA analysis by researchers at 23andMe, Harvard University, and the Smithsonian Institution has revealed more about the enslaved and freed African Americans who labored at a Maryland iron furnace, just after the founding of the United States. 

Along with insights into the lives of these forgotten people, the study leveraged 23andMe’s large research database to find connections between these people and more than 40,000 of their living relatives.

The stunning analysis published the journal Science reveals a hidden history. Moreover, it provides a technical and ethical benchmark to inform future studies of a similar, largely forgotten burial sites.

“Our study demonstrates the power of DNA to uncover important history about the lives of people whose stories are lost to time,” said lead author Éadaoin Harney. Ph.D., a 23andMe scientist on 23andMe’s Population Genetics R&D team. “The study revealed more about these individuals, including identifying familial groups, discovering details of their ancestral origins in Africa, and connections their history to people living today.”

Connections to Early American Industrial Site

The researchers looked at the DNA from the remains of 27 individuals, many of them teenagers and children, extracted from a cemetery at the historic site of Catoctin Furnace.

Among them are 15 related individuals clustered into five family groups, which were mostly made up of mothers, their children, and siblings. The remains of those related individuals were generally found buried near one another.

Their DNA indicates that these individuals had more ancestry connecting to a region now known as Senegal and Gambia and, more specifically, groups from that region, such as the Wolof and Mandinka, than do most modern-day African Americans.

Many also had European ancestry, mainly from Britain and Ireland, likely due to the rape of enslaved African American women by their white enslavers and others in position of power (who had primarily European ancestry). Further evidence of that exploitation was that much of the European ancestry was on the paternal side.

The highest concentration of the Catoctin individuals’ closest living genetic relatives are in Maryland, indicating that some surviving family member of those who labored at the forge remained in Maryland since the late 1700s or early 1800s.

Reconnecting to Lost Roots

Harvard geneticist David Reich helped oversee the study along with Douglas Owsley, curator of Biological Anthropology at the Smithsonian. The Smithsonian’s National Museum of Natural History is the custodian of the remains, while scientists at Reich’s lab handled the extraction and testing of the DNA.

Harney, who completed her PhD in Reich’s lab before joining 23andMe to facility this collaboration, and other 23andMe researchers designed and implemented an approach to compare the genomes in the Catoctin individuals with DNA from over 9 million 23andMe customers who consented to participate in research.

As a result, the scientists identified more than 42,000 living relatives. Most of these relatives are distant, and a much smaller portion have a closer relationship. The closest matches were likely 5th-degree relatives, equivalent to a great, great, great grandchild.

History Revealed

Like hundreds or thousands of African American burial grounds across the country, the history of those who were buried at Catoctin Furnace could easily have been lost. There were no inscribed headstones, and many of the stones that marked the graves had been moved. The forgotten burial ground at Catoctin Furnace was first unearthed in the 1970s during construction of a new highway in Fredrick County, Maryland, and the remains were placed in the care of the Smithsonian.

In previous studies, anthropologists at the Smithsonian were able to identify physical ailments from which the Catoctin individuals suffered through examination of their skeletal remains, such as a hip deformity that left one young woman with a lifelong limp, a man with a bent and fused spine, and a teenager with multiple, comprised vertebrae, likely due to heavy manual labor.

Related Articles on FamilyTree.com:

International African American Museum Launches Genealogy Center

Smithsonian National Museum Of African American History & Culture

Tips For Researching Your African-American Ancestors

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