Anyone Can Now Take This Breast Cancer Gene Test, But It Probably Won’t Tell You Much

Breast and ovarian cancers are scary, anxiety-provoking diseases, and with good reason. Although breast cancer isn’t the cancer that kills the most women (lung cancer holds that distinction), it is the most commonly diagnosed cancer in women. And ovarian cancer is difficult to find in its early stages. But anyone willing to spit in a tube and pay $199 will soon be able to find out if they have a particular genetic predisposition to either of these cancers.

This month, the FDA granted the genetics company 23andMe permission to offer direct-to-consumer testing for three of the more than 1,000 known variants of the genes BRCA1 and BRCA2¹ that have been found to confer an increased risk² of breast and ovarian cancer. (The tests were previously only available through a doctor.)

But not everyone is celebrating. Because the gene variants found by the test are extremely rare, most people who take the test won’t come away with much meaningful information, and there’s no good evidence that people who take the test will be better off than those who don’t.

What we have is a clash of philosophies: Should consumers have a right to information that some experts have deemed unhelpful and potentially harmful for most people (if it gives a false sense of security to those who test negative or increases anxiety)? Proponents of consumer testing say “yes.” The debate centers on how decisions about genetic testing should be made and who is entitled to a say.

One thing that there’s agreement on: The vast majority of women diagnosed with breast and ovarian cancer don’t have any known genetic factors. Only about 5 percent to 10 percent of breast cancer cases and 10 percent to 15 percent of ovarian cancer cases³ occur in people with a BRCA1 or BRCA2 gene variant. And the gene variants themselves are rare. The mutations detected by the 23andMe test are present in far less than 1 percent of the general population. They’re more common in women of Ashkenazi Jewish descent, but even then, they still appear in only about two out of 100 of those women.

AT LEAST THE DOCTORS HAS DONE SOMETHING ABOUT CANCER BECAUSE IT IS DANGEROUS

for more information visit:

https://fivethirtyeight.com/features/anyone-can-now-take-this-breast-cancer-gene-test-but-it-probably-wont-tell-you-much/