Part 2: The Zygosity Test Results Arrive

O Brother, What Art Thou?

Part 2: The Zygosity Test Results Arrive

O Brother, What Art Thou?

Part 2: The Zygosity Test Results Arrive
A couple of things.
Aug. 24 2011 1:26 PM

O Brother, What Art Thou?


Russell and Barry Harbaugh.
Russell and Barry Harbaugh

Do you long for a story of mistaken identity? In college, I wrote a short play about a pair of twin brothers sharing a bed. One wore football pads and a helmet, the other my best approximation of hipster chic. A sealed envelope lay beside the bed containing the outcome of a genetic zygosity test. This was at the height of a Pinter phase, and the ensuing pages were rife with what I imaged was a subtle, violent rage that weighted everything with subtext. When a couple of friends read the script aloud for the rest of the class ("Should we open it?" "No. Yes." "Oh, fuck you."), I cried inconsolably in the back row.

A sudden phone call from Julia, an employee of Affiliated Genetics, had prompted the memory. The eight deposits of our spit—smeared onto two pieces of white cardboard paper, each divided by a four-squared grid—arrived in Utah only a day ago. I had assumed the results would come back in an envelope that I could open, ignore, or burn. But no sooner did Julia state her affiliation that I felt a lump somewhere under my breastbone, roughly the size and density of a peach's pit. I nearly hung up.


"Yes?" I whined.


We brought this upon ourselves. Russell and I tried very hard to cultivate individual interests and attitudes. Without surveying the various parenting fashions of twins in history, I might point out the school of thought that demands parents dress their identical children in matching outfits, parting their hair on opposite sides (like a mirror's reflection!), and just as well the school filled with parenting books advising the opposite.

However we came to it—whether through a mother's growing devotion to those books, or some innate desire on our part to complement each other—Russell and I have long attached ourselves to different things, and driven each other crazy with a manic desire to report in detail whatever the other missed.

In 2002, we went off to Wabash College together, a fine all-male school devoted to forging "gentlemen" in upstate Indiana, and one that I stomached for a year before transferring home. The decision was unilateral and it stung. So too: a trip I took that summer to Europe, alone. By sheer coincidence, his football team traveled to Vienna in July, to play an exhibition, and Russell got a tattoo on his left shoulder blade from a man he met in a bar, while I watched. An R whose leg has been cleaved in half so that with a bottom curl it also conveys a B, it proved an unreciprocated mark.

Whether or not we had actually split from a single life form, here was the split that mattered. No more living down the hall. No more seeing each other every day. Would we talk as often? What would we miss? How could we exist as separate entities?


Fraternal twins rarely, if ever, think themselves as alike as two peas. Far more often, misdiagnosis occurs when identical twins think themselves unalike—"of a family likeness only." (In other words, fraternal twins don't question their zygosity; it's the identical ones who get confused). You may have heard that Mary Kate and Ashley Olsen—twins so alike that they have shared professional lives since they were 6 months old, most notably by pretending to be each other without any of their millions fans noticing—have long declared themselves fraternal. What can one say other than: Bahooey.

As I waited for my own results to come through, I contacted every lab I could find that does this sort of commercial twin testing. I wanted to find stories of identical pairs who had thought themselves fraternal, or of twins that had no idea either way. The search turned up one pair of girls who had grown up with a triplet brother, and couldn't believe the identical result they received: "I never did feel like I was looking at a reflection," one of the sisters wrote. "When the truth finally came out my mom was shocked. She was the mother, how could she get it wrong?"

But when I asked for help finding a pair that had thought themselves identical, only to discover otherwise—and I shook the bushes for two weeks, badgering labs all over the country—I was met each and every time with silence. Affiliated Genetics, which has been testing for zygosity since 1994, didn't have a single adult twin on record who received a heterozygous result. Not one pair (remotely around my age) had ever tested as fraternal. It seemed nothing short of astonishing. Not one? Where are all the dizygotic wannabes, vainly dressing in matching overalls?

It's enough to make you wonder about this whole business with the buccal smear. The companies advertising in Twins magazine and vying for keywords in Google's sidebar ads, give mostly the same pitch: Doctors have for years handed out misinformation and erroneous opinions upon seeing the placenta; now you can know for sure.

But what those Swedish questionnaires reveal is that in most cases you can know for sure without the benefits of modern science. If it's even plausible that you're identical, then that's almost certainly what you are. My brother and I have nothing at all to gain from a positive response. Our relationship cannot be fortified by still more evidence of something we've assumed since the Terre Haute sandbox. Certainty, the mere idea of certainty seems like a threat—that we either didn't know ourselves well enough to shrug off the allure and presumed authority of a DNA comparison, or that we just don't know ourselves. What we have to lose is nothing short of the grounding conceit of our whole lives.


"I'm calling with the result of your zygosity test," Julia said. "The result is monozygotic. You and your brother were concordant in all 15 STR markers."

I felt not so much relief as a new indifference. Any other result would have been impossible. I asked her how the test worked, what the markers were. She didn't know. She suggested I speak with someone in the lab. I never did; I don't think I will. Let the genetic mystery at least have its code.

I planned to keep the news from my brother and study his reaction as I lorded it over him, but a few days after I'd taken the call, we went to an old friend's wedding and I couldn't last even halfway through the reception. He didn't react much more than to raise his eyebrows. We clicked our plastic flutes that I'd just retrieved from the bar, muttered cryptophaisicduhs, and moved on to something that didn't seem so obvious. How on earth had we mistaken this putrid apple cider for champagne?

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A big thanks to Robert Jackson at ProActive Genetics for wrangling twins for the quiz. He couldn't find any fraternals, but he tried.

Barry Harbaugh is an editor at Harper.