Genetic Testing

Genetic tests offer a way to find out whether people are at risk for particular diseases. Research has shown that cancer, diabetes, heart disease and countless other disorders may have a genetic link. Genetic tests can help individuals learn whether they have a mutation that may lead to a disease.

Many types of genetic testing are available. One popular test is carrier screening. This test checks your dominant and recessive genes to determine whether you carry any disorders that could be passed to your children, even if you don ‘t show any symptoms.

Other tests are used for:

  • assessing the risk of cancer, Alzheimer ‘s and other serious conditions
  • confirming symptoms
  • health risk assessment
  • identifying disorders such as Huntington ‘s disease before symptoms appear
  • identity testing
  • newborn screening
  • pregnancy risk assessment
  • prenatal screening.

The Genetic Testing Process

If you ‘re considering genetic testing for yourself or your child, you probably have a lot of questions about what is involved.

Genetic testing is a pain-free way of finding out whether you are at risk for developing a genetic disease. Tests are available from various sources, but the fastest and most convenient is by a direct purchase.

The lab technicians will require a sample of your DNA. This sample can be from any tissue, although the most common samples are cheek swabs or saliva.

The lab technicians scan your DNA sample for any mutated sequences. Often, they also compare the DNA in your genome to a normal, healthy gene and look for differences.

The cost of genetic testing ranges from several hundred to several thousand dollars, depending on the size of the genes and the number of mutations tested. Check with your insurance provider to see whether genetic testing is covered under your plan. Keep in mind, though, that health insurance providers have access to your results if they cover any part of the cost.

Interpreting the Results

When you get your test results, you ‘ll find out one of two things: either you have the mutation you were tested for, or you don ‘t.

Having a mutation does not mean that you will definitely get a disease. In other words, testing positive for a genetic cancer mutation does not mean you have cancer. It simply means that you have a heightened risk compared to the general public, based on your genetics. Most disorders stem from a combination of genetic and environmental factors, so you can take steps to reduce your risk.

Neither does a negative result mean that you will definitely not get the disorder. It means that you have the same risk as the general population: nothing in your genes indicates that you have a higher risk.

Discuss your results with your doctor is important. Your physician can help put your results in perspective, recommend options for lowering your risk and talk about any fears or concerns you have.

Benefits of Genetic Testing

Genetic testing can save lives. Finding out that you are at risk for a disorder gives you the chance to take steps to prevent the development of that disorder. For example, a person with a high risk for cancer may get more frequent screenings. Cancer has a higher survival rate if caught early.

In addition, testing can help couples decide whether to have children. If they discover that their potential child has a high risk for a genetic disease, they may choose to adopt instead.

Risks of Genetic Testing

Genetic testing in its current form has several drawbacks, including:

  • anxiety caused by the results
  • lack of available medical options for some diseases
  • limitations of testing, including human error
  • potential discrimination based on results
  • problems interpreting a positive result.

If people who undergo genetic testing try to interpret results by themselves, they may misunderstand the information. They may avoid seeing a doctor out of fear that a negative result will be confirmed. That is why discussing your results, positive or negative, with your doctor is so important.

Resources

Genetics Home Reference (2008). What is direct-to-consumer genetic testing? Retrieved November 18, 2008, from the Genetics Home Reference Web site: http://www.ornl.gov/sci/techresources/Human_Genome/medicine/genetest.shtml.

Humane Genome Project Information (2008). Gene testing. Retrieved November 18, 2008, from the Genomics Web site: http://www.ornl.gov/sci/techresources/Human_Genome/medicine/genetest.shtml.