In the 1970s, Robert Jenkinson was newly married with a daughter, looking for a job and in need of extra cash. He settled on sperm donation as a way to allay the last of those concerns while helping other families have children. He never could have expected that, because of DNA testing, the day would come when he would be contacted by the children he helped create. Needless to say, neither could anyone else, including the sperm banks that historically promised anonymity to donors. Over the past few years, the number of children Jenkinson learned he had helped conceive through donation has grown, as more and more of them have found him through commercial databases. At last count, he reported 22 genetic children, and he was cautiously and thoughtfully feeling his way toward relationships with those who wanted to know him.

We live in the age of genetic reckoning. It’s now remarkably cheap and easy to spit into a vial or swab your cheek and find out about your genetic relatives and ancestral history. Most of the time, the results are merely interesting. But in a significant minority of cases, the information is life-changing, answering questions people never thought to ask, like: “Is my father genetically my father?” In the decade or so since home DNA testing companies began offering products with the power to identify what are sometimes called “DNA cousins,” this technology has begun to profoundly change the American family.

It’s time to examine how home genetic testing is starting to reshape how we relate to one another. While reporting “The Lost Family,” my new book about home DNA testing, I came to believe that the effects of this technology — which play out in vastly different ways for different people — may be moving us toward a more inclusive definition of family. In future years, I think we’ll look back on this as the liminal moment, the point when commercial genetic databases reached a saturation point and reconfigured how Americans understand kinship and identity, not to mention how we think about truth and the past.

Well over 30 million people have swabbed their cheeks or spit into vials through companies like AncestryDNA, 23andMe, MyHeritage DNA and FamilyTreeDNA, receiving results about their ancestral histories, their genetic cousins, and their risk for conditions like celiac disease, Alzheimer’s and certain kinds of cancer. Even with a recent slowdown in “spit kit” sales, more and more people will join these databases in coming years. Based on my interviews with genetic genealogists, population geneticists and other industry observers, my conservative estimate is that at least 1 million people who’ve engaged in recreational testing have experienced one of two significant surprises in their results: that the man they call Dad is not their genetic father or that they have a previously unknown half-sibling. (A Pew Research Center study last year found that more than a quarter of testers discovered a new “close relative,” a looser definition that would put us closer to 10 million consumers experiencing such a revelation.)

If you consider all the people in a family affected by this kind of surprise, including those who didn’t take a DNA test, you’re talking many more millions of people. Discovering that one’s parent isn’t a genetic relation is so common that it’s known among testers by its abbreviation, NPE — for “non-paternity event” or “not parent expected.”

How is this transforming us? DNA revelations can be heartbreaking and confusing and uplifting and clarifying, sometimes all at once. They may cause rifts in families, or they may reconstitute them — prompting loving reunions between newfound siblings or between adoptees and birth mothers. They may lead to grievous rejections when those being sought by genetic kin don’t want to be found. They alter people’s personal narratives. They create major upheavals in their lives, upheavals that — as I found in talking to interviewees over the course of a year or more — continue to play out over time. They prompt people to rethink past, present and future.

The discovery that one’s genetic identity isn’t what one believed can be traumatic, even as most people say they are deeply grateful to know the truth. Krista Driver, a therapist who learned through DNA testing that the man she knew as her father wasn’t genetically related to her, says the emotions she and others have experienced can include grief, anger, guilt and anxiety about the loss of identity. “It’s like being unmoored, it’s being untethered,” she told me. Several people I interviewed used this same “lonely boat” metaphor to express the aloneness and disorientation they experienced when encountering major surprises. “I felt adrift, I didn’t know who I was,” the protagonist of my book told me. “I felt like somebody just stuck me on a raft and pushed me out to sea,” another interviewee told me.

As chief executive of the nonprofit Mariposa Women and Family Center in Orange County, Calif., Driver started counseling groups for others who’ve experienced NPEs, and she’s one of a few mental health professionals carving out this new area of treatment. In the future, I believe this area will be a common subspecialty, just as some psychologists and social workers now specialize in anxiety, PTSD or divorce counseling. This is sorely needed because, while consumers can find community with others online, primarily in Facebook groups, there is little in the way of formal help or expertise available for them. In the future, more groups may arise like NPE Friends Fellowship, a nonprofit dedicated to support and education around this phenomenon. Recognizing that DNA surprises have grown more frequent, the major testing companies have specialized customer-care representatives for more sensitive calls, and 23andMe last year added a page to its website titled “Navigating Unexpected Relationships,” linking to online therapy resources like BetterHelp and Talkspace.

What’s more, in years to come, there may be more people like Brianne Kirkpatrick, a genetic counselor outside Charlottesville who works not only with people who’ve received DNA surprises — offering guidance on how they can reach out to biological kin, for instance — but also with people keeping genetic secrets. She advises parents of donor-conceived children, for instance, on the importance of telling them the truth about their origin, both because those children deserve it and because DNA testing will inevitably reveal it. And she coaches them on how to have those conversations. Already, parents are far more open about things like donor conception and adoption than they were decades ago, and DNA testing is furthering such disclosures.

We may also develop more and better language to describe DNA surprises. Some terminology already peppers the many Facebook support groups — testers talk of learning of their NPEs, while the donor-conceived use the acronym DC, and some identify themselves as DC-NPE. We may also come up with ways of referring to, say, siblings discovered late in life. Language is important — not to lessen the significance of such relationships; family is family, after all — but because these connections come with their own gifts and challenges, and this phenomenon deserves to be named.

In my conversations with more than 400 consumers of genetic testing, I’ve been deeply moved by the beauty, care and emotional nuance people bring to navigating the new relationships testing reveals. Stories from early adopters of this technology, now five or 10 years into their reckonings with the truth, demonstrate that it’s possible to honor two fathers, both the man who raised you and the man who contributed half your genes. Of course, there are people who decline to have relationships with relatives they discover through testing, and there can be complex and painful reasons for that. But overall, this technology’s unexpected consequences may inspire us, as a culture, to become more openhearted about all the ways a family can be formed, and less binary in our thinking about genetic bonds on the one hand and the bonds of love, intention and experience on the other.

This cultural moment comes as the landscape of consumer genetics testing is shifting. Even before the pandemic, AncestryDNA and 23andMe announced layoffs as sales of their spit kits slowed down. Experts say that’s because they vacuumed up all the early adopters — the people predisposed to spend $100 to augment their family research — and because potential consumers may have privacy concerns. Yet families will continue to be affected because the databases will continue to grow, especially as the major companies try to find new markets by offering testing for health and for genetic traits like food preferences and hair color.

It’s important — urgent, even — that we start a conversation about how these revelations are reshaping lives, not only for the million-plus people already affected, but for those of us who will never take a DNA test but whose relatives will. In other words, if there’s a genetic secret in your family, you will find it out in the next few years, if you haven’t already. Which means we all have a stake in understanding what the future of the American family looks like.

Twitter: @libbycopeland