The obvious benefit of genetic testing is a better understanding of your risk for a certain disease. Testing is not perfect, but it can help you make decisions about your health.

A negative result on a genetic test in families at risk for a specific cancer may relieve uncertainty. In the same way, a positive result can help you make important decisions about your future. A positive result may lead to finding disease earlier and preventing deaths.

Testing can help learn the prognosis (outlook) for a person diagnosed with cancer, and can even help with deciding which treatments are most likely to work. As scientists learn more about the genes that contribute to cancer, genetic testing will probably become more helpful in learning about a person’s risk for a disease.

What are the drawbacks of genetic testing?

Genetic tests have several potential problems you must think about before being tested:

Limited answers

Genetic tests do not give precise answers about inherited diseases, especially about breast and colon cancer. A positive test result does not always mean you will get the disease. The test can tell what might happen, but it cannot tell what will happen. On the other hand, a negative result does not mean you have no risk of getting the disease.

A test may also be flawed, or test results may be read wrong. Genetic testing is not tightly regulated, and different labs may have different ways of looking for a certain mutation.

Sometimes a genetic test may be done even though the result has little chance of helping the patient. When this happens, the test may create anxiety when the original intent was to relieve it. This is why counseling before you get the test is so important — you’ll want to know exactly how the result will help you, and if it will help enough to make up for the stress it can cause.

Psychological or emotional impact

Many people are anxious even before they get their test results. They may think about how the result might affect them and their families, and how they can talk about and manage it.

Learning that you have or might develop a serious disease is frightening. The person being tested may find it even more upsetting if family members have already died of the disease in question.

A positive genetic test can also affect other family members. More family members may need to be tested. Sometimes family secrets are revealed as a result — paternity, adoptions, or other difficult issues may come up.

Having a gene or passing a gene on to children can bring out feelings of guilt or anger. The test result can affect future relationships with a spouse or other family members, which can be stressful, too.

In some cases, more medical tests or procedures may have to be done as a result of genetic testing. For example, if a gene mutation for colorectal cancer is found, more tests like colonoscopy may be recommended. These extra tests can also be sources of stress and anxiety.

Privacy issues

Most people who ask about the privacy of genetic information are concerned about how the information may be used in ways that can harm them. Most Americans are afraid that employers and insurance companies might get and use their genetic information. They fear an employer could find out and discriminate by not hiring or promoting them, but the GINA law forbids most employers from doing this. (See the next section, “National law prohibits discrimination by employers and health insurers.”) Some people are even concerned that adoption efforts could be stopped based on this type of sensitive information.

On the other side, some companies and researchers are concerned about there being too many restrictions on this information.

The privacy issue becomes even more complicated when so many family members may be affected by a single positive genetic test result.

For these reasons, it’s important to think about who might learn about your results and who you will want to share your results with before you decide on testing.

National law prohibits discrimination by employers and health insurers

The Genetic Information Nondiscrimination Act (GINA) went into effect on May 21, 2009 for insurers and on November 21, 2009 for employers with more than 15 employees. It bars discrimination based on genetic information by these employers and health insurers. GINA defines genetic information as:

• A person’s own genetic tests
• The genetic tests of family members
• One or more family members known to have a genetic disease or disorder

Employers: GINA bars employers from discriminating based on genetic test results or genetic information. GINA states that employers must not discriminate on the basis of genetic information in hiring, termination (firing or layoffs), pay, or other personnel actions such as promotions, classifications, or assignments. The law applies no matter how they got the information.

Employers may not require genetic testing and may not collect genetic information except for very limited exceptions. For instance, it may be allowed when information is needed to meet the requirements of family and medical leave laws or to watch for harmful effects from hazardous workplace exposures.

Employers must keep genetic information confidential. They may not release or share genetic information except for when:

• The employee asks them to
• Fulfilling a request from a health researcher
• Complying with medical leave law
• Disclosing or reporting to a public health agency

Health insurers: GINA bars health insurers from turning down people or charging higher premiums for health insurance based on genetic information or the use of genetic services. This includes genetic counseling and testing.

GINA bars group health plans, individual plans, and Medicare supplemental plans from using genetic information to limit enrollment or to change premiums. It also bars these insurers from asking for or requiring genetic tests. GINA applies to all health insurance plans (including federally regulated ERISA plans, state-regulated plans, and private individual plans).