When I was a young boy, I found a photograph half-hidden in the back of my parents’ closet, leaned up behind my mother’s stacked boxes of high-heel shoes. A dandyish man in a dark suit and skinny tie stared out at me, bearing a striking resemblance to my mother. Who was he? His hair, parted neatly in the middle, peeked out under a broad-brimmed hat perched jauntily on his head. In time, I learned that the unknown man was my grandfather James Morgan Richardson. But not until I was 16, when I overheard a conversation between my parents in the middle of the night, did I learn that he was white.

My parents kept my grandfather’s portrait hidden because in 1960s Mississippi, with all its racial paranoia, displaying the picture in our living room would have been risky, if not impossible. Severe social consequences awaited any black person claiming close kinship with a white person. So the picture stayed hidden, part of my mother’s past, and my own—something I knew about but didn’t yet feel free to explore.

My mother knew that the portrait fascinated me, and when I got married, she gave it to me. I saw that gift as an invitation to learn more about the man within the borders of the frame. It has taken me 20 years, but I’ve finally begun to figure things out and better understand my own history as well.

In 21st-century America, my family would be described as multiracial. But in the world I grew up in—the American South of the 1950s and 1960s, where the idea of race and identity determined who you were and your place in the world—you were either black or white. We were first colored, later Negroes, and still later black. Claiming mixed status meant you were either trying to be white (implying that black was inferior) or trying to pass for white (a dangerous business few spoke of openly), and doing so carried the risk of being labeled a racial traitor. Consequently, my identity was shaped by the racial boundaries of the American South as well as the double consciousness that W. E. B. Du Bois speaks of in The Souls of Black Folk. I always felt that duality: “an American, a Negro; two souls, two thoughts, two unreconciled strivings; two warring ideals in one dark body, whose dogged strength alone keeps it from being torn asunder.”

My mother was seven years old when her mother died. The town doctor who pronounced my grandmother dead offered to help the family start over as a white family, far away from their small town in rural, isolated south Alabama. Even though my grandmother Edna Howell Richardson was black, all her children’s birth certificates said they were white. So, this “transformation” would have been easy. But in the end my grandfather, the man whose portrait had been hidden in the closet, chose not to hide his children’s mixed race. Instead, my mother and her sister grew up going to black schools and identifying as black. When they married black men, they had to have their race officially changed on their birth certificates in order to get legal marriage licenses.

I grew up hearing my mother say, “You can always tell when someone is passing.” Since she could pass for white, my mother spoke from a position of authority. Racial passing, once a common subject of discussion in the black community, has faded from American consciousness with the emergence of racial and multiracial pride. But even today, with six multiracial grandchildren of her own, my mother stands by her statement: “You can always tell.”

Once, in 1967, she spotted an old classmate from Tuskegee Institute who was managing the men’s furnishings section of a Mississippi department store where, a few years earlier, black people weren’t allowed to try on clothes, much less work above the position of elevator operator. Black people couldn’t even work as clerks in that store, so the man could not have moved up to this level unless he was passing. When my mother recognized him, he was fussily arranging a display of memorabilia from southern schools. She strolled over to take a look, remarking, “Why, I don’t see anything from my school here.”

The man replied with steely silence, carefully maintaining his composure.

Then my mother asked him point-blank, “Do you have anything from Tuskegee? I’d like to get something for my husband.”

The man turned beet red, quietly said no, and tried to smile his way through my mother’s attempt to “out” him. In her inimitable southern manner, my mother responded with fury cloaked in sweetness: “Well, I thank you so much for checking.” From that day forward, the man avoided my mother whenever she walked into the store, and each time, her eyes shot in his direction, casting that knowing glare upon him.

When I look back on this incident, I realize that my mother reacted the way she did because she saw this man as a traitor of the highest order. He had turned his back on the philosophy of racial uplift he had been taught at Tuskegee; the oppressed had assumed the role of oppressor. And all this during the height of the civil rights movement. Given the times, and my mother’s history, I can understand her anger.

In spite of her being mixed race, in spite of having been raised primarily by her white father, being black remains the core of my mother’s identity. Perhaps to keep from confusing my siblings and me, she didn’t tell us about her father’s race until the four of us were all nearly adults. So, for many years, I had to pretend that I hadn’t overheard my parents talking in the middle of the night—talking about how hard it had been for my dark-skinned father to ask a white man for his daughter’s hand. And I had to pretend, as well, that I hadn’t seen the portrait hidden in the closet.

My family’s complex racial history, filled as it is with myths and truths, led me to DNA ancestry testing. I had begun writing a book on the life and times of my maternal grandparents, whose marriage around 1915 was an act of defiance in a part of the South governed by Jim Crow laws. In that book, The House at the End of the Road, my purpose had been to tell the little-known story of mixed-race families in the American South, like my mother’s, that prevailed in spite of Jim Crow and laws against interracial marriage. As the book took shape, a scientific study caught my eye.

In late 2005, scientists reported the discovery of a gene mutation that had led to the first appearance of white skin in humans. Other than this minor mutation—just one letter of DNA code out of 3.1 billion letters in the human genome—most people are 99.9 percent identical genetically. And yet, what divisions have arisen as a result of such a seemingly inconsequential genetic anomaly. Moreover, this mutation had separated members of my family along tightly demarcated racial lines for three generations. As this discovery became known, I was invited to join a class on race relations at Pennsylvania State University in which all the students participated in DNA ancestry testing as a way of discussing contemporary attitudes about race and cultural identity.

Through the DNA tests, students came to realize that the racial or ethnic identities they grew up with were sometimes in conflict with their genetic material, belying the notion of racial purity. In class, I listened to students talk about racial labels and identities, and whether ancestry testing had changed their perceptions of themselves. Most embraced the newly found diversity that their DNA test revealed, and none felt that ancestry testing had changed their personal identities. Still, the discovery of mixed ancestry was a struggle for a few. One white student wondered whether her African heritage came from “a rape in my past,” and another thought that her African DNA must have come from “promiscuous family members.” These comments were indicative of the stigma that any hint of African ancestry carries for many white Americans. No one suggested that racial passing—which I’d immediately brought up in the discussion—might explain some of these traces of mixed heritage. Only one student even seemed to understand the idea of racial passing. He grew up in an interracial home, with a father of Jamaican descent and an Irish mother, and he was close to both sides of his family. Although issues of race were discussed openly at home, he told me, no one ever forced him to choose between being black and being white. And in spite of having fair skin, he did not claim to be white, choosing instead to forge his own identity as multiracial, thus embracing his phenotypic ambiguity.

When the instructor, sociologist Sam Richards, asked whether I would be interested in taking my own DNA ancestry test, as part of a larger DNA study being conducted by anthropologist Mark Shriver, I did not hesitate to say yes. Given that I already knew my mixed-race background, the results weren’t shocking: 60 percent West African ancestry combined with 32 percent European, six percent East Asian, and two percent Native American. The East Asian ancestry was the only surprise, but Mark explained that Asians and Native Americans are closely related evolutionarily. (Several years later, I took a second and more sophisticated DNA test that revealed slightly different results: 50 percent African, 44 percent European, and six percent Asian. These two sets of results are within the margin of error.)

Outside Mark’s office at Penn State, I studied a wall of photographs showing the faces of various people from his DNA study, from Penn State and around the world, each image accompanied by the ethnic designation that person identified with. Beside the photograph was a paper flap, which, when lifted, showed what a DNA sample revealed about that person’s ethnic background. As I went through photograph after photograph, few of the personal ethnic identities matched the DNA profiles. Most people had some mixture of DNA from at least two groups; many, like me, had genetic ancestry from Europe, East Asia, West Africa, and Native American groups. Blond people had African and Asian ancestry, and several dark-skinned people had more than half of their DNA from Europe.

What we see when we look at a person may or may not correlate to his or her ancestral and ethnic background. DNA results confirmed for me that identity cannot be constructed based on a “percentage” of African ancestry, and that our society’s generally accepted racial categories cannot begin to address the complexity and nuance of our heritage. I soon began to think about race only in terms of culture and biology together. And as race became an abstract rather than a concrete concept, the categorical ways in which I had thought about race in the past were quickly broken down. Once we see how small the differences are that bring about the characteristics we think of as racial—hair, skin color, eyes, facial features—in relation to the entire human genome, it’s hard to make a fuss about them. Our differences are astonishingly slight.

Around this time, I was immersing myself in the work of philosopher Kwame Anthony Appiah and especially his books Cosmopolitanism and The Ethics of Identity. I’d begun to make distinctions between my personal identity and the collective dimension of identity that comes from society. When you accept that race is socially constructed—that being African American is a collective identity developed outside one’s self and is therefore not within one’s control—race matters less. DNA ancestry testing made that idea much clearer for me. It highlighted the flawed logic underlying the American concept of race based on standards of purity and superiority, since very few people have DNA that comes from only one part of the world. More important, it confirmed for me how many people have several cultural identities, not just one. The way I saw myself did not change, but DNA ancestry testing helped me abandon the racial myths that had shaped the first part of my life. I was moving away from the very limiting vision that divided the world into “us” and “them.”

I began thinking about how firmly my own children’s identities were rooted in the post–civil rights era. My three children are multiracial—my wife is of Irish, Swedish, and Swiss-German descent—and they grew up talking openly about race and cultural identity. They knew all about my parents and grandparents. Moreover, we live in Washington, D.C., until recently a majority black city but one with constantly shifting ethnic and social demographics. Given the diversity of our city, my children’s identities have been shaped in an environment more rarefied than less-urban parts of the country. What would a DNA ancestry test reveal to them? Excited about my own experience, I asked my eldest son, Patrick, who was born in 1992, to take an ancestry test and to tell me how he felt about the results.

I imagined we’d have a vigorous discussion about how DNA turns the historical concept of race upside down. But for my son, the traditional concept of race had already been overturned, and our discussions revealed a deep generational gulf between us. As in my case, the sources and percentages of my son’s ancestry were not surprising: 72 percent European, 25 percent African, and three percent Asian. But when I mentioned how revealing DNA had been to me, Patrick just shrugged his shoulders, as if the numbers meant little to him. “They don’t change the way I think of myself or the way I view the world,” he said. “When people ask me, ‘What are you?’ I generally tell them that I am American. And given how diverse my background is, it’s in my way of thinking, a background that could only come about in America.”

My wife and I had fielded “what is he” questions about Patrick over the years, particularly when he was quite small. Patrick is very fair-skinned, with light brown hair. Up until his teen years, he was so blond that people sometimes assumed that my dark brown–haired wife and I had adopted him. Once, a visitor to my wife’s office, glancing at a family picture, asked insistently why we had adopted one of our three children, pointing directly at Patrick. “I gave birth to that child, believe me,” my wife responded quite sternly to her incredulous visitor. “No, that one,” he insisted, pointing to Patrick, “is definitely adopted.” This man believed that a child who looked like Patrick was a genetic impossibility, based on our appearance and my ethnic background. If he had seen the wall of photographs hanging outside Mark Shriver’s office at Penn State, he might have better understood how hard it is to judge “identity” on looks alone.

“What I tell people depends on the assumptions someone makes about me,” Patrick told me. “Since I am from D.C., people will ask me what it was like for a white kid to grow up in a black city or will launch into a series of stereotypes of black people. I’ll tell them it was pretty easy growing up in D.C., since I am black. Then I watch the shocked disbelief on their face. If someone appears to have no real agenda when they ask me, I tell them that my mother is white and my father is black.” Patrick said he never gets into the complex racial mix on my side of the family, with a white great-grandfather and a black great-grandmother, both of whom had blond hair and blue eyes. “Still, I always make it clear I am not white. I’ve tried not to fall into that fear of belonging to a single group that many people have, even though I know race is not a real thing and just something people have made up over time to define themselves.”

Since Patrick is a college student, the conversation about “what he is” sometimes moves toward a discussion of science and a belief in evolution, in the context of generational differences. “We’re asking ourselves better questions now,” he said to me. “The science that drove discussions of race in the last century was conducted to maintain the status quo and affirm stereotypes. That’s the one thing DNA changes.” And yet, I kept coming back to Patrick’s indifference to his DNA ancestry test. “Seeing that I have ancestry that can be traced back to Mesopotamia is pretty cool,” he said, “but for the most part, I’d put DNA ancestry testing on the ‘meh’ list. Your DNA test may have deconstructed race for you, but my DNA test had no real impact because race has already been deconstructed for me—and has been my whole life.”

I grew up in a world of racial boundaries; Patrick grew up free of a repressive racial calculus. Therein lies the difference between us. Two sets of test results inside one family; two markedly different responses. And not because of the numbers, but because of what those numbers mean (or do not mean). Because of how we read them, because of the context of our lives, our different moments in history.

According to the 2010 census, the number of multiracial children in the United States has increased in a decade by 50 percent to 4.2 million people, making multiracials the fastest-growing youth group in the country. Across the country, nearly three percent of the population chose more than one race on the last census, a change of about 32 percent since 2000. In the South and parts of the Midwest, the growth of the multiracial population has increased more than the national average. In my native Mississippi, the multiracial population grew by about 70 percent, and the state had the largest increase in interracial marriage of any state since the last census. Still, the multiracial population of Mississippi is only 1.1 percent, and many Mississippians see the legacy of the state’s racial inequities as part of the cultural mindset. That’s not hard to understand, given that less than half a century ago interracial marriage was illegal in Mississippi. Neighboring Alabama—where my grandparents lived—removed the constitutional prohibition against interracial marriage only in 2000, with 40 percent of Alabamians voting to keep the prohibition in place.

How do we get people such as those who voted against interracial marriage to focus less on the concept of race and more on the concept of humanity? As Mark Shriver remarked when we discussed my DNA test results, “You can defuse traditional thinking about race by making people see these differences as natural and teaching them that the differences are just part of the variety of life. That’s the trajectory we are on regardless. How quickly we get there depends on how good a job we do in educating people to this new way of thinking.”

What is left once we have deconstructed race, and what does such a concept mean for the present and the future? Racism is easy when only two races exist in any significant numbers, as has generally been the case throughout American history. Multiple and overlapping ethnicities (with none in the majority) make racism more difficult. In the 19th century, the eventual path to acceptance for the Irish, Italians, Eastern European Jews, and to a certain extent, Asians who immigrated to America, was to become “white.” This option was uniquely closed to African Americans. In a more diverse and racially mixed America, “becoming white” may no longer be a key to equality. That may be the biggest, most significant change in American culture over the next generation.

Demographically, we are becoming less white and more multiracial, and have a larger population of Hispanics and Asians. Moreover, Hispanics complicate America’s simplistic black-white dichotomy: they do not fit neatly into either racial category. As Amitai Etzioni pointed out in a 2006 essay that appeared in these pages, if “Hispanics continue to see themselves as members of one or more ethnic groups, then race in America might be pushed to the margins.” And yet, American cultural discourse on race is still stymied by a tainted racial past largely divided between black and white. For more than a century, America built a racial caste system, a concept originally invented to categorize perceived biological, social, and cultural differences. Though that system has been eroding for decades, our changing demographics require a swifter transformation. Our rapidly expanding multiracial and Hispanic populations do not signal the end of race as a concept, but they do open up new possibilities for how we think, talk, and understand the subject. And talking about race—engaging in the sort of frank and open discussions that I witnessed at Penn State—is precisely what we need more of at the moment.

Such dialogues will, alas, likely take place only within a small part of our population. Too many people are still in the thrall of cultural myths. Having grown up with many of those myths, I recognize their power to divide and to cause harm. And yet, I no longer look at a person and think I can presume to know his race, ethnicity, or background, or whether he is claiming a race other than the one into which he was born. Increasingly, I believe that it is unethical to engage with another person solely on the basis of race or ethnicity.

Perhaps it all goes back to the man in the portrait at the back of my parents’ closet. Before I knew he was white, I thought he was just a cool-looking guy. I didn’t know why he’d been relegated to the back of a closet. There was no flap to lift on his portrait, as with the photographs on the wall at Penn State, to reveal what percentage of his makeup came from this part of the world, or that. Maybe part of what appeals to me about DNA testing is that it helps show how much all of our portraits are composites, and reminds us how much better it is to expose those portraits than to hide them away.

I still see myself as a black kid from Mississippi, but first and foremost, I think of myself as a member of the human family. Embracing this idea has allowed me to reconcile ways of feeling and of comprehending race previously clouded by my personal history. I like to think that W. E. B. Du Bois would be pleased that I no longer feel held back by unreconciled strivings. As Du Bois wrote in 1909 in his biography of John Brown, “the cost of liberty is less than the price of repression.”