Gene Testing Often Gets It Wrong

BarbaraHudson writes: ABC is reporting that gene tests for risk of specific diseases are not as accurate as we'd like to think, with different labs giving different interpretations. Over 400 gene variants that could help one make medical decisions regarding breast and ovarian cancer or heart disease have different interpretations from different labs according to the study. "The magnitude of this problem is bigger than most people thought," said Michael Watson, executive director of the American College of Medical Genetics and Genomics, one of the study's authors. Researchers caution consumers to be careful when choosing where to have a gene test done and acting on the results.

Comments

I wouldn't hire him, then

[wonkey_monkey]

Gene Testing Often Gets It Wrong

Maybe Mr Testing should pay more attention to his work.

Bayes rule

[cowdung]

If a 99% accurate test is true, but the probability of the condition is only 0.0001%, it is still highly improbable that the person is afflicted by the condition on the basis of the test alone. Its important to narrow down the population before any testing is effective.

Re:Bayes rule

[lars_stefan_axelsson]

If a 99% accurate test is true, but the probability of the condition is only 0.0001%, it is still highly improbable that the person is afflicted by the condition on the basis of the test alone. Its important to narrow down the population before any testing is effective.

Yepp. It's not for nothing that the first thing a doctor will tell you as the answer to the "What do I do now"-question that inevitably results from a positive test is: "Have more tests".

Initial screening tests are often less accurate, since that inevitably makes them quicker and cheaper. That's why they're called screening tests. The odd positive results is just confirmation that better, slower, more expensive tests should be done.

Headline versus article

[tomhath]

The article says more data will improve accuracy, and advocates collecting and analyzing more data. Seems pretty reasonable compared to the scary sounding "Often Gets It Wrong" headline..

Re:Not the testing, the interpretation.

[Rich0]

Agree. It seems like a simple solution is to unbundle the testing and interpretation.

This is really no different from any other area of testing. A lab can assay the creatinine in my blood, or the microalbumin in my urine, or the concentration of glucose in my blood. Those results are likely to be very accurate and reproducible unless the lab is just criminally negligent.

What those results mean is an entirely different matter. A doctor will certainly utilize those results as well as the results of many other tests, history, interviewing the patient, and so on to make a diagnosis, and refine it as more data comes in.

Just make the labs, well, labs. Now you can certify them far more objectively.

Money

[Tokolosh]

This is about the big-dog incumbents (Myriad Genetics, Quest Diagnostics), who charge upwards of $4,000 for testing. They are concerned to keep out small companies that are trying to disrupt the business with $250 testing. With modern technology there is no reason it should cost any more, including interpretation.

The tactics are patents, lawsuits, lobbying and FUD.

https://en.wikipedia.org/wiki/...
https://www.aclu.org/cases/ass...

Re:Now he tells me

[davester666]

no big. you weren't using it anyway.