When genetic tests are basically horoscopes

Fantastic piece in today’s Inside 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.)

I suspect that this will mostly be interpreted as an indictment of the athletics genetic testing “industry.” And, they seem to deserve it. But there’s a bigger issue here: many similar companies enter the market with laughably limited evidence that their “personalized recommendations” are actually informed by science.

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.

I’m sensitive to the idea that [the long time it takes to generate] evidence frequently slows the process of bringing innovative tools to market. However, this is a helpful reminder that speed can also disadvantage consumers (while rewarding founders).