Around the World in 46 Chromosomes
“And he made from one man every nation of mankind to live on all the face of the earth, having determined allotted periods and the boundaries of their dwelling place, that they should seek God, and perhaps feel their way toward him and find him…” Acts 17:26–27
My heart beat rapidly with excitement when I received the email proclaiming that my DNA results had been analyzed. But nothing could prepare me for the surprise I experienced when I clicked the link that would take me to my results.
Colored circles lit up the world map showing me where my ancestors had ancient origins. Not surprisingly, a large blue circle highlighted East Asia—my mother was born in Korea and adopted as a child by a family in Missouri. What caught me off guard was the circle around West Africa.
According to my results, 20 percent of my DNA originated in what is today Nigeria, while another nearly 18 percent came from other parts of Africa.
Growing up, my assumptions were all wrong, according to this, and my emotions swirled around trying to make sense of it. Yet I was also grateful: This knowledge about my own life would not be possible if it weren’t for recent advances in DNA testing.
In the last few years, as scientists have developed a way to easily compare large datasets of DNA, curious people have begun taking advantage of affordable autosomal DNA tests, which focus on autosomes—the 22 pairs of chromosomes that do not determine sex. I jumped in. I’m a second-generation adoptee, so my quest is to learn more about both sides of my family.
My adoption records say that my mother, who was 20 years old when I was born, did not know who my father was. Out of three potential biological fathers, one was Mexican and the other two were European American.
So, with my darker toned skin and thick, curly hair, I had assumed my whole life that the only logical option was Mexican. I had speculated how much indigenous ethnicity my father brought to the table. I even took Spanish, in part to learn the language of my father’s country.
While the mystery of my origins isn’t completely solved, this DNA test was a big clue that perhaps his being “Mexican” was not the whole story. It turns out that the story is much more rich, varied, and profound.
In some sense, I had always felt like an ethnic anomaly of some kind; no one else I knew had the ethnic makeup that I did. My adoptive parents were both 100 percent German American. In many ways, I even felt like a “new American.” As far as I was aware, my roots in the US extended back no further than one generation.
This DNA test proved something in a tangible way what I hadn’t understood before: I was connected, not only in the US (that’s small beans) but also in the historic world—God’s huge family of wonderfully created people. He made this possible by fashioning DNA to pass on to our descendants—a fundamental code that determines hair color, eye color, and, of course, much, much more—using 23,000 genes spread across 46 chromosomes, half from each parent. We carry this information on from generation to generation as it changes and combines in new and different ways, creating something unique.
In an autosomal DNA test, like the one I took for discovering ancestry, a mathematical formula is used to compare results with others for differences in these genes and predict genetic distance (second cousin, third cousin). The closer the relationship, the higher the level of confidence. As the Ancestry.com website began to fill out with more DNA test takers, the social aspect of the site kicked in and I began to get more DNA “matches.”
Surprising to me, many of my fourth and fifth cousin matches were European American, even though only about five percent of my DNA originates there. Technically, it is difficult to prove beyond a second-cousin connection for people like me whose parents did not procreate within the same gene pool. To prove genetic connection to these people, DNA testing known relatives should also be done (of course that wouldn’t be easy for me).
But the point stands: Within a few short generations I am connected to families all around the world—families whose everyday experiences are much, much different from my own.
The test allowed me some theoretical daydreaming: According to the test, one percent of my genes came from the Iberian Peninsula, one percent are Native American. Was there something to the “Mexican” in my adoption records? Were my ancestors African slaves traded by the Spanish instead of the British, as many African Americans can trace their origins? How did I have Pacific Islander DNA? Or European Jewish?
As I looked over my DNA connections, profile pictures of my genetic family stared back at me: skin shades from ivory to ruddy to tan to black, straight and curly hair of all kinds, five o’clock shadows, braided hair, and all manner of fashion. Did John Smith or Jane Doe even suspect they had a half-Korean, half–African American fourth cousin? Without DNA testing, it’s probable they would never see that connection.
Some might consider me to be unique, the anomaly. But this same connection is illustrated in many others’ lives with the aid of autosomal DNA testing. In 2012, geneticists from the PBS show Finding Your Roots found the average degree of separation between the two dozen guests who appeared on the show was only three—much closer than the popular game Six Degrees of Kevin Bacon suggests.
Ironically, Kevin Bacon, who was on the show, is connected genetically to Condoleeza Rice, Cory Booker, and Geoffrey Canada. In fact, 23andMe, which does the genotyping for Finding Your Roots, estimates that any two of its users will be connected to each other as fourth or closer cousins.
Bridge figures in the human story of migration and social interaction connect otherwise seemingly homogenous people groups, breaking through social conventions. Throughout history, our social groups have played a powerful role in determining our DNA. We mate with whom we associate, and we tend to associate with similar people. Sociologists have called our tendency to associate with people most similar to us as homophily, which means love of the same.
Indeed, people have gravitated toward being in groups of sameness since Babel, drawing lines of difference. According to a 2001 sociological review, race and ethnicity contribute to the strongest divides in our social worlds, separating us more than age, religion, education, occupation, gender, or anything else.
A couple hundred years ago, the divide was explicable. In 1800, though many people still crossed racial lines in one way or another to produce children of mixed race, only three percent of people lived in cities, where cultures have historically convened. Most people never met another person who spoke a different language, and never had an opportunity to do business with or worship alongside people of another origin.
Today, 7.3 billion people inhabit the world—all of whom can be divided into 7,000 language groups, 194 nations, and any number of ethnic groups (a distinction that is fuzzy). And in 2007, the number of people living in cities passed 50 percent for the first time in human history. People live closer than they have before. Long-distance travel is easier and cheaper. The world is at our digital fingertips. Yet we still live in silos.
“Consider New York, where residents know that Brighton Beach is home to thousands of Russian speakers, Flushing to a large Chinese community, Borough Park to Orthodox and Hassidic Jews,” Ethan Zuckerman, a media scholar, writes in his book Rewire: Digital Cosmopolitans in the Age of Connection. “The promise of our contemporary cities is that it’s possible to encounter different foods, customs, and ideas through incidental encounters with neighbors or through the conscious decision to take a subway ride to a different corner of town. But how often does this happen?”
The DNA test is an illustration of the amazing connection we share with others quite different from ourselves. It’s just a hint of the intended relationship that exists in God. “Then God said, ‘Let us make man in our image, according to our likeness…’” Right from the beginning, when the first man and woman received their DNA code—the potential for all the diversity of man— his image was in us.
In these tiny genes arranged carefully in a particular order, we are actually closer to each other than we often feel. Ties by blood are enduring, despite varying languages, cultures, and nations. Together, we are in fact the image of God. Of course, there’s still division, pain, sadness, tragedy, and horror in those genes, but the message is still right there, whispering to us: There is grandeur there, too. Thousands of genes expressing not only the beauty of God’s creativity but the wonderful connection we all share as humanity.
Rebecca Randall is The Behemoth’s new science editor.
- Editor's Note from February 18, 2016
Issue 42: A surprise DNA test, an unexpected power plant, and a breakthrough chirp. /
- Why Solar Power Might Get a Lot More Green
It turns out that Popeye was right all along. /
- Music of the Spheres
When scientists detected gravitational waves, “astronomy grew ears.” /
- Little Blessing for My Floater
“This tiny ruin in my eye” /
- Wonder on the Web
Issue 42: Links to amazing stuff.