Genetic experts warned women who will take the first direct-to-consumer breast cancer test offered by 23andMe that if they get positive results, they can be placed in a tailspin if they are not ready to make life-changing decisions. The genetic testing company got the green light on Tuesday from the US Food and Drug Administration to provide a breast cancer risk report without a prescription.

The approval makes 23andMe the first DTC genetics test to provide information about a woman's genetic risk for cancer. It specifically refers to three mutations to the BRCA1 and BRCA2 gene. The typical cancer genetics test needs a doctor's prescription and tends to be more in-depth beyond the three mutations, Business Insider reported.

Ancestry and health components

When a patient orders a test kit – which costs $199 for the ancestry and health components – she will receive a saliva collection tube that she has to send back to 23andMe laboratories. The lab analyzes the contents and will generate a wide range of reports based on information about the ancestors of a patient and how the patient metabolizes. It will include other health risk reports for conditions such as Alzheimer's disease and celiac disease.

The 23andMe DTC test will specifically look at mutations to the BRCA1 and BRCA2 genes that are connected with an increased risk of breast and ovarian cancer in women and breast and prostate cancer in men. Since the three BRCA mutations are most commonly found in people of Ashkenazi Jewish descent from eastern Europe, the test has little use for women who are not of Jewish background, Mary Freivogel, the former president of the National Society of Genetic Counselors, said.

But Anne Wojcicki, the CEO and co-founder of 23andMe, said that the test is incredibly valuable for women who might not be aware that they are of Ashkenazi Jewish descent or are not familiar with a family history of cancer. She also stressed that the majority of cancer is not hereditary.

Even if the test results are negative for the three genetic mutations, the BRCA1 and BRCA2 genes have thousands of mutations that can mess up how the genes work. There is a possibility that a woman has another mutation which the test excluded.

Because the Ashkenazi Jewish population is a very small part of the US population and world population, Dr. Kenneth Offit, the chief of the clinical genetics service at Memorial Sloan Kettering Cancer Center, said he never found the mutations in anyone other than an Ashkenazi Jewish person, Time noted.

But a positive result does not mean the patient has cancer. It only means she is at a higher risk for breast and ovarian cancer. If a woman has a mutation in her BRCA1 or BRCA 2 genes, her chance of having breast cancer goes up by 50 percent from only 7 percent for American women without the mutation.

Most well-defined mutations

However, Kathy Gibbs, the chief legal and regulatory of 23andMe, pointed out that the three mutations are among the most well-defined when it comes to the BRCA1 and BRCA2 genes. She recommended women who have a family history of breast cancer to take a more comprehensive, doctor-ordered test that searches for more mutations in the BRCA1/2 genes and with other genes associated with cancer.

Freivogel cited the experience of a friend in her mid-20s who asked her doctor if she should undergo regular breast cancer screenings since she has a family history of breast cancer. When the DNA test that her doctor suggested came back positive, and the physician began asking questions, the woman was not prepared to answer such as having a preventive mastectomy and having children soon because of the need to remove her ovaries.

Setting expectations

To help set some of the expectations, Freivogel suggested for the patient to complete first an educational module before they view their 23andMe test results for BRCA1/2. In the case of the Alzheimer's and Parkinson's disease test of 23andMe, patients must opt-in to receive the reports when they order the test and once they receive the results.

Gibbs advised women whose results yield positive for one of the mutations to talk with a healthcare professional about options for screening and prevention. She added that it is important for the results to be confirmed in a clinical setting before the women initiate any medical action.

For women whose test results will show they are negative for the three mutations, they will still get a message that says the genetic variants that 23andMe tested may not be the cause of most cases of breast and ovarian cancer. However, they are still at a risk of developing these two cancers. The patients will be told to undergo any further cancer screenings that their healthcare provider may recommend.

Dr. Banu Arun, the co-director of the clinical cancer genetics program at MD Anderson Cancer Center, said her concern is over people who order the test without consulting with their healthcare provider. If they get a negative result, it can give them false reassurance.

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