Gene Testing Often Gets It Wrong 37
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.
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no big. you weren't using it anyway.
jolie did (Score:2)
Medical Decisions (Score:1)
My mom found out from a geneticist that she was at risk for breast cancer, so she preemptively had a double mastectomy. My father found out he was at risk for heart disease, so he had a cardiectomy.
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Fire the geneticist. Your genes can't tell if you're at risk for any cancer. They can only tell if you'll have a greater risk than the average human. Acting on anything found by your genes at this point is just stupid at best.
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Fire the geneticist. Your genes can't tell if you're at risk for any cancer. They can only tell if you'll have a greater risk than the average human. Acting on anything found by your genes at this point is just stupid at best.
The major breast cancer genes give the patient somewhere around an 80% chance of getting breast cancer, which in my book is close enough to certainty when death is a possible outcome.
However the associated chance of ovarian cancer is only around 50% which makes for a much harder choice for a younger woman, as having your ovaries removed would cause immediate menopause, with its own serious life changing effects.
I wouldn't hire him, then (Score:5, Funny)
Gene Testing Often Gets It Wrong
Maybe Mr Testing should pay more attention to his work.
Bayes rule (Score:5, Interesting)
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.
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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.
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11 percent have been analyzed by more than one lab so results can be compared. In 17 percent of those cases, labs interpreted the findings differently, as either raising the risk of a disease, having no effect on it or having an unknown effect.
So what do you do - get 3 tests and let the majority inform your decision?
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From that we have an estimate that a minimum of 17% gene variants are misclassified by at least one lab. Just because the different labs agreed does not make those classifications correct. Also just because a risk is raised does not mean the correct response is some preventative action (raised how much?), so the correct action could still have been taken. Or not.
Another thing is that from that news article we have no idea how many actual tests this would invalidate, we only know the percent of gene variants
Not the testing, the interpretation. (Score:2)
Re: Not the testing, the interpretation. (Score:1)
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Re:Not the testing, the interpretation. (Score:4, Informative)
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.
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Headline versus article (Score:4, Insightful)
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An investigative TV news program here did their own study - sent samples from the same people to different labs, and got back different results. The tests do often get it wrong.
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Every test and every interpretation has a margin of error; obviously a person should understand the error rate for both false positive and false negative is before making a decision. The headline simply said "often gets it wrong" but I don't see any qualification of what "often" means. One in ten? One in a million? Who knows? Although they do state that some labs are more competent than others; no surprise there.
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On the plus side... (Score:2)
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So is every single other human being on the planet.
If you're talking about being descended from Charlemagne, it's only exceedingly (if not astronomically) likely - it's not an absolute certainty.
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Which tests were more or less accurate? (Score:1)
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This isn't the first time either - up here investigative tv journalists sent samples from each test subject to several different labs and the companies refused to be interviewed to explain why the results came back different depending on which company did the test.
Testing for "risk" is risky (Score:2)
Skin in the game (Score:2)
Call me when someone is offering genetic testing with some consequence to them if they get it wrong. Until then, this should be treated as if it were a scam.
But science KNOWS humans are causing global warm^H (Score:1)
Every day we read about how science doesn't have it's shit figured out as much as we thought, but damnit, CLIMATE CHANGE IS HUMAN CAUSED 100%.
Never mind that giant ball of (deadly) nuclear waste in the middle of our solar system. (remember, nuclear power is bad, kids)
Money (Score:4, Interesting)
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/... [wikipedia.org]
https://www.aclu.org/cases/ass... [aclu.org]