At first glance the DNA ancestry “craze” may seem like yet another navel-gazing fad cleverly monetized by the tech industry. But personal genetic testing is much more than a kind of Snapchat filter for your family album.

By combining the complex science of DNA testing and the data riches uncovered by the Human Genome Project into an accessible, relatively inexpensive self-testing kit, the genetic heritage industry has created an ingenious product: a consumer must-have that tickles one of the deepest, most ancient and potent of human wishes. This wish is not, as it happens, to have scientific proof of your genetic heritage. The beguiling promise that these ancestry kits offer is the possibility that you just might be someone else.

Not that I, like most folks, consciously walk around wishing I were living someone else’s life. Nor are the tests, as objects, lust-inducing: there’s not much industrial design involved with the little cardboard boxes, no beguiling surfaces, rounded corners or hip insignia. But after many months of being unsure of why I wanted – no, needed – a genetics test, I broke down, spent the cash and spit in the tube.

The kits, which generally retail for around $99 – MyHeritage just launched a competing kit for $79 – are packed with a test tube to spit in or Q-tips to swab your cheeks and a pre-addressed padded mailer. If you feel like splurging on something more glamorous, for $199 you can buy the National Geographic Society’s kit, which tests your ancestral DNA to discover, among other things, if you’re part Neanderthal.

The craze to discover your DNA roots isn’t a particularly American phenomenon: India is in the midst of a boom, Living DNA, a British startup, claims to trace customers’ ancestor DNA to a regional level, and ancestryDNA is available in 29 countries (including Vatican City).

When I got the results of my DNA test – which were exactly what I had expected – a powerful feeling of disappointment flooded through me. I felt silly, but I didn’t care about scientific proof that confirmed who I am. I really wanted those results to surprise me.

I know I’m not alone with this feeling. One of the great human fantasies that riddles the narratives of global cultures from prehistory to today is that, like baby Moses in his basket, Harry Potter under the Dursleys’ staircase, Luke Skywalker on Tattooine or Cinderella with her bucket and mop, we are not who we seem to be. And the ancestry DNA kits stir up the powerful unconscious wish that we are meant for a greater, or at least, a different, destiny.

Perhaps not everyone, certainly, but many of us, have had the experience of looking around a dinner table or a subway car or a laundromat and being sure that we are not where we are supposed to be or with our people.

Which is actually true for some people. Holocaust survivors, adoptees and African Americans have fraught and difficult relationships to this powerful technology. But that is not my story.

Nor did I relate to writer Maud Newton’s reasoning in her essay examining the American DNA ancestry fad, that: “The discovery that I am almost exactly as white as I have always appeared was deeply, irrationally disappointing”. Newton ascribed her disappointment to a kind of shame about her forebears’ behavior that might have been “mitigated” by a different genetic result.

I am more of a recreational ancestral DNA tester, if you will.

But human curiosity is formidable. Like my ancestors before me, who paid crystal-ball gazers in the Middle Ages or commissioned people to interpret star charts, I spit in a tube and waited for it to reveal its hidden truths: who I really, really am; what secret grand ancestors lie hidden in my DNA. But then the spit was sent to a lab tech, not a kind woman at a carnival who would tell me what I was aching to hear – that I’m special, from a long line of special people.

Unless you are someone who has been cut off from your origins, the ancestry kits (most often) will provide you with scientific proof that you are pretty much who you think you are. Your life isn’t a fable; you weren’t switched at birth; your exasperating family really is the one you’re stuck with forever. And just like your mom always said, Uncle Bob’s need to play the bagpipes on Thanksgiving is more about Uncle Bob than about any family ties to Scotland.