-I'm mostly British. -I'm Chinese-American.
-Also, French, German. -I am Mexican, I am Spanish,
I am American, and I an Venezuelan.
-Half African-American.
-Teeny, tiny trace amount of Nigerian.
-Half Puerto Rican.
-So far as I know, I'm 100% Irish.
-I can trace my ancestry back to bills of sale from slavery.
-I'm a New Yorker and an American
and a descendant of Eastern European Jews.
-Having a blended ancestry is a big part
of what defines most of us as Americans.
We all know that we're a mix of different cultures
and people from other parts of the world.
For many black Americans, charting your ancestry back
to a specific country has always been a mystery.
And that's a testament to slavery.
-The interest is uniform across the human species,
but the ability to reconstruct was severely impeded
by the transatlantic trade in enslaved Africans.
Genetics helps to restore some of the lost information,
but we know more
about Neanderthals than we know about Africa.
-Our fascination with the mixture of cultures
and people that make up who we are as products
of a country that's a melting pot
is a part of why ancestry kits like 23andMe and ancestry.
com are so popular.
And answering that question, for African-Americans,
of "where did we come from?"
revolutionized the way geneticists look at DNA
to chart ancestry.
And all of that started right here in New York City.
In 1991, construction workers at a federal building site
in Tribeca stumbled across human remains
from an African burial ground from the 1600s and 1700s.
Back then, New York was a British colony
that relied heavily on chattel slavery.
42% of households owned enslaved people there,
making it the largest slaveholding city
in North America, second only to Charleston, South Carolina.
Africans in New York at the time held on to their culture
through burial ceremonies near a lake
in what is now Lower Manhattan.
When the plot was rediscovered, experts estimated
that over 15,000 people were buried there,
and almost half of them were children under the age of 12.
Rediscovering the burial ground
stirred up a lot of emotions for New Yorkers.
It forced them to take a critical look
at how slavery played a role
in creating the city they know and love today.
For descendant communities,
it meant that they had an opportunity
to have a say in how slavery is memorialized here
and also play a role in the research
that's conducted on the remains.
Michael Blakey was enlisted as the scientific director
to answer some of their questions.
And one of their main questions was,
"Where are these people from?"
-They had a culture all their own
before they were brought and enslaved in New York.
They wanted to know about those cultures.
-The remains were sent to Howard University's Cobb Laboratory,
where geneticist Dr. Fatimah
Jackson started trying to answer some of those questions.
Her team cut open skulls from 419 bodies
that were exhumed from the site.
So, are there specific parts of different bones
that you go to to harvest genetic material?
-Oh, yeah.
For the genetic material, the best part is right here.
This is the petrous bone.
See this kind of triangular-shaped bone?
-Mm-hmm.
How is the DNA right here different from, say, a femur?
-It's just that it's more dense.
The bone is more dense, so there's more DNA
packed into this area.
And my research group has developed a technique
to extract this in about four cuts.
They mark it, they cut it, and then they pop it out.
-Once harvested, DNA from the petrous bone was extracted
and compared to a database of samples
from humans all around the world,
using the exact same process commercial ancestry kits
use today to pull DNA from saliva samples.
But the results were off.
-There were a number of inconsistencies.
It seems unlikely that a European would slightly file
his teeth or Native Americans would wear waist beads,
be buried with a pipe that is Nigerian.
So what we were finding is that, you know,
it is certainly possible for the DNA to be wrong.
-Up until this point, genetic research primarily focused
on trying to figure out mixtures
between geographically disparate areas as a proxy for race.
So how African are you or how European are you
or how Asian are you?
And how does that show up in your DNA?
The problem is, biologically speaking,
race doesn't actually exist.
-We're just one race. Sapiens is our race.
We're all Homo sapiens sapiens.
That second "sapiens" is actually our racial designation,
from a biological point of view.
All diversity that exists among modern humans exists
below the "racial level."
We've had these notions that are more a product
of our political and economic priorities
than scientific realities.
-No one had ever asked the question
that the descendant African-American community
asked us to ask of our data,
which was, what were the origins of,
essentially, African America?
So geneticists had never asked that question,
and the databases were not set up to answer it.
-Shifting the question from, "How African are you?"
to "Where in Africa are you from?"
meant that they needed to go back to Africa
and collect a more diverse pool of samples.
Dr. Jackson and her team
went to Cameroon
and set up the very first DNA bank in Africa
in order to help bolster their databases.
-We would try to tie the genes
that we were finding to the ecological setting,
and that gave us a road map for reconstructing
where people in the diaspora had come from.
-The burial ground played a huge role
in teaching geneticists about both biases in their field
and gaps in their catalog of DNA reference points.
And in the case of commercial ancestry kits,
the picture is still very much so incomplete,
especially for descendants of people
who were enslaved in America.
So, is this the basis of commercial DNA ancestry kits?
-The commercial companies do not have
a continental African database
that is needed to make the kind of connections
that we have for North Atlantic European ancestry.
We're at the beginning stages of understanding
the human genome, not at the end stages.
-The African burial ground was memorialized in 2007
by the National Parks Service,
and the monument itself bears the markings
of some of the different countries and cultures
that have blended together to make our unique ancestry
as Black Americans.
DNA might not be able to answer all of our questions
about where we came from,
but it does offer an opportunity to gather more information
and reclaim that narrative.
What do you think that means or tells us
about what it means to be black in America?
-The commercial tests are beginning to unite Americans
in ways that they did not expect.
You know, people from, ostensibly,
different ethnic populations who are your relatives
because the genes don't really discriminate in that way.
They don't care about the color of your hair
or the skin color or anything like that.
We know that the interpretation of the data has been lacking
because of the reference databases being limited.
But what genetics forced us, as a people --
it's not just African-Americans, but all Americans --
to confront our own history,
and, in doing so, we understand ourselves better
and the choices that our ancestors may have made
that allowed us to exist today.