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I have a genetic variant that predisposes me for high aerobic fitness. Or else it’s low aerobic fitness. I’m not actually sure, because I took two mail-order genetic tests that interpreted the same spot in my DNA in opposite ways.

Maybe I should just listen to a third test, which interpreted the same genotype to mean I’m wired to benefit from eating scrambled egg whites, quinoa salad, and stir-fry chicken on Sundays.

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I found myself in this hall of mirrors after taking five of the most popular genetic tests marketed directly to athletes — both high-level competitors and recreational joggers like myself. The tests promised to analyze elements of my genetic makeup to deliver “unprecedented insights” about my “fitness potential” or help me “achieve optimal wellness and body composition.” But some of the tests flat-out contradicted each other, delivering different interpretations of what certain regions of my genome meant for my risk for tendon injuries, for instance, or my propensity for high blood pressure.

I went into this process genuinely hopeful that the tests might explain why I’m good at certain sports. (Back in high school, I was a serious softball pitcher.) I hoped, too, that they’d offer helpful tips to improve my athletic skills now.

Along the way, I endured seven vials of blood drawn from my arm in one sitting. I accidentally made my inner cheek bleed. And I stumbled upon information about my Alzheimer’s disease risk that I had never wanted to know.

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Alex Hogan/STAT

And for what? Not much of value.

As I learned, there’s very little solid research about how to interpret genetic markers that relate to fitness on an individual level. And there’s virtually no evidence to support how athletes should act on the information.

That’s likely why the information I got back was either dismayingly general — common sense advice like stretch well before exercise — or oddly (and, to me, improbably) specific, like the menu telling me to eat quinoa on Sundays.

Here’s what I learned about myself and this industry from these tests:

Reading a horoscope

Just deciding which tests to order was overwhelming. At least 39 companies marketed fitness-oriented consumer genetic tests last year, nearly double the market size in 2013, by one researcher’s count.

I ended up ordering tests from DNAFit, Genomic Express, Kinetic Diagnostics, Orig3n, and Simplified Genetics. They ranged from $154 to $400 in price.

The tests arrived in the mail over the next few weeks. Each box contained a swab and instructions about how to rub it against the inside of my cheek to collect a sample of my DNA. (I laughed at one advisory not to swab too hard — before promptly drawing a bit of blood.) Kinetic Diagnostics also sent me to a nearby lab to get seven vials of my blood drawn; I must have looked squeamish because the technician asked more than once if I was OK. I later learned the blood was analyzed for a section of the report focused on non-genetic biomarkers, such as vitamin levels and cholesterol.

I mailed my cheek swabs back to each company, and eagerly waited for my results.

Alex Hogan/STAT

In the subsequent weeks, my genetic information streamed into my email inbox — and, in the case of Orig3n, into a sleek smartphone app. I got data tables, charts — and stock photos of focused athletes.

Each test reported on between 2 and 57 of my genetic variants, rendered as a two-letter genotype, like CC or AT.

Scouring the reports, I felt sometimes like I was reading a horoscope. I looked for signs of myself that I could recognize: My apparent immunity to tendon injuries. My preference for short sprints over long steady runs. The long arms that gave me an edge as a softball pitcher — or the slim build and poor coordination that disadvantaged me.

I didn’t find much of that.

Most of what I got back was, frankly, dull. And supremely unhelpful from a practical perspective.

Kinetic Diagnostics, for instance, told me I have six variants that increase my risk for osteoarthritis — and four more that put me at typical risk. Orig3n told me I have five variants that predispose me to have a normal metabolism.

Wired for softball?

Most of all, I was curious to see if the tests would offer insight as to whether softball — a hugely important part of my life growing up — had been the “right” choice for me genetically. I made some of my closest friends playing the sport. I spent endless hours on the field. And by the end of high school I had gotten pretty good.

Was I wired for that passion?

To my disappointment, I didn’t get anything that specific from any of the tests I took.

But it’s probably for the best: When such tests first started hitting the market about five years ago, many were marketed as a way to match kids with their genetically ideal sport. Many of the companies thriving today, however, have steered clear of such controversial prescriptions and instead simply report that various genetic markers give advantages or disadvantages for endurance sports or “power” sports (which generally involve quick bursts of speed).

Problem is, some people are somewhere in the middle. Like me. All the tests that analyzed my variant of the gene known as ACTN3 agreed: I could succeed at either power or endurance sports but have no strong advantage for either one. In other words, I’m kind of boring.

Genomic Express did give me a list of six sports, from basketball to water polo, that “require endurance but for which power provides an advantage.” (Softball was not among them.) But the company was careful to note that DNA is not destiny: “You can certainly increase your performance in all types of events through proper diet/nutrition and training regimes.”

Blitzed with common-sense advice

OK, got it. So would the genetic tests help me find my optimal diet and training regimen?

In a word: no.

Alex Hogan/STAT

The tips I got back were almost comically generic. One piece of advice from Kinetic Diagnostics on how to compensate for my increased risk of muscle cramping? “Do proper stretching and muscle warm ups before and after exercise.”

DNAFit’s recommendation to make up for a variant that predisposes me to to see fewer gains from endurance training? “Stay sufficiently hydrated.”

Kinetic Diagnostics said I was at elevated risk of high blood pressure; DNAFit said I was likely to experience fewer problems with blood pressure. They both offered the same advice, supposedly tailored to my genotype: exercise.

(When I later asked them about this recommendation, the companies acknowledged that such advice could benefit anyone but insisted that people with my genotype would find it especially useful.)

The tips that seemed most specific came from Simplified Genetics, which recommended that I divide my weekly exercise into three high-intensity workouts, like sprints or a step class, and one low-intensity workout, like yoga or hiking.

But I found the advice suspect, because it was based on analysis of just two variants on a single gene. (Simplified Genetics CEO Kurt Johnsen told me the two genetic markers provide an entry point to get customers on the right track.)

The company also mapped out a week-long meal schedule for me that Johnsen said optimized the distribution of fat, protein, and carbs for my genotype and gender. It featured a breakfast smoothie on Monday, a turkey salad lunch on Tuesday, and a dinner of tilapia and quinoa on Wednesday.

It all sounded perfectly healthy, no doubt, but I had a hard time believing a single gene made this particular menu more ideal for me than any other menu full of healthy foods.

A tangle of contradictions

Then there were the interpretations that flat-out contradicted one another.

The tests each looked at different regions of my genome — which may have been necessary to distinguish themselves from their competitors, but which in and of itself suggests just how much this field is in its infancy. So it wasn’t possible to compare the complete results from each company head-to-head.

But among the scores of data points, I found 20 genetic variants that showed up on two or more test results. The companies all gave me the same genetic readout on those variants, so I have little doubt they correctly analyzed the cells in the cheek swab I’d sent them. In six cases, however, the interpretation I got from one company directly contradicted the interpretation from another.

And in one case, two companies cited the same journal article to support their opposing conclusions.

Conflcting DNA test results
Alex Hogan/STAT

This happened in their analysis of the gene known as COL5A1, which regulates the production of a protein found in tendon and ligament tissue. The three tests that reported it agreed that I have a genotype of TT. That’s a relatively rare variant, found in less than 10 percent of the population, according to Orig3n.

DNAFit said that made me more vulnerable to tendon injuries, citing a few studies. Kinetic Diagnostics agreed that I was at greater risk, citing a different study from 2012.

But Orig3n took that same 2012 study and came to the opposite conclusion: I’m protected against tendon injuries.

At this point, my head was spinning.

So I got in touch with the authors of the 2012 study, who said that their results “are too preliminary for confident interpretation” of what my TT genotype means for injury risk.

And, to my surprise, Orig3n CEO Robin Smith conceded that his company had likely got it wrong.

After I told Smith about my findings, he said his team reviewed the literature and concluded that most likely, I was at greater risk of tendon injury after all. He pledged to send out a correction by email to other customers with the same TT genotype. And he told me his team would study the data on another genotype where Orig3n’s interpretation contradicted another test.

How did the other companies respond when I asked them about this and other contradictions?

DNAFit sent me a 2,000-word document defending its interpretation of my genotypes. It even included quotes from scientific studies to bolster its interpretations — and to rebut the contradictory results I got from other companies. (My apologies to the DNAFit staffers who got stuck with that task.)

Kinetic Diagnostics didn’t respond to my specific questions about the contradictions. It has since withdrawn the test I took from the market, describing it as a “pilot,” and is working on refining its business model.

A weighty disclosure

There was also some off-the-wall stuff in my results.

My Kinetic Diagnostics test told me that my DNA makes me more likely to try cigarettes. (For the record, I never have.)

A supplementary genetic assessment I ordered from Orig3n, branded as the “Superhero” test, told me I “take longer to learn new languages.” (To be honest, Spanish and Italian weren’t my strong suits in school.)

Harvard geneticist Dr. Robert Green has a very skeptical view of companies who say they can tailor athletic advice on the basis of someone's DNA. Alex Hogan/STAT

I also received some weighty information I wasn’t expecting. A few months prior, I had reported on the sometimes wrenching decision some athletes make to get tested for two variants on the gene known as APOE, which is the most well-studied genetic predictor of Alzheimer’s risk.

It was something I knew I never wanted to learn about myself.

Then I happened upon my APOE status, innocuously billed as an indicator of how likely I was to be overweight, in the pages of Orig3n’s Fitcode test. I noticed immediately that I carry a relatively rare variant — rare enough, I knew, to be linked with either an increased or reduced risk for Alzheimer’s. My heart started pounding in my chest.

It only slowed down when I did a quick search to learn that I carry the variant that appears to be slightly protective against Alzheimer’s in some populations. But I still felt a strange sense that I had gained intimate and unwanted information about myself.

Orig3n was the only company that hadn’t published on its website a list of the specific genes it would be looking at. Smith said the company had no qualms about including APOE because it wasn’t analyzed in the context of Alzheimer’s, but was used to tell me I have normal cholesterol metabolism.

So how did peering into my genes change me?

I haven’t made a habit of Wednesday-night quinoa. And I can’t profess to have altered my exercise routine too much.

But before running the other day, I might have spent a little more time stretching. It certainly couldn’t hurt.

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