Genetic Testing Definition

Genetic testing, genetic engineering, gene therapy — DNA seems to be at the root of so many scientific buzzwords lately. But with all the hype about genetics and genetic testing, it can be difficult to separate truth from reality. Before you consider having a genetic test done, you’ll want to have a solid understanding of the process, and know what you can (and can’t) uncover by decoding your DNA.

Genetic testing can be used for the following:

  • forensic or identity testing
  • paternity/maternity testing
  • screening embryos and newborns for genetic disease
  • screening potential parents to see if they are genetic disease carriers
  • testing adults for genetic disease (either before symptoms are present, or to confirm a diagnosis)
  • testing for matrilineal or patrilineal heritage for the purpose of uncovering ethnic roots and tracing a family tree.

Its important to understand that in the case of disease risk, genetic testing results arent absolute and dont serve as a diagnosis on their own. However, they can be extremely useful for the purpose of informing health decisions and lifestyle choices.

What is Genetic Testing?

Its a common misconception that because genetic testing is so telling, it must be invasive and painful. In fact, its neither- human DNA is available via hair and saliva samples as well as blood samples. Many labs can uncover information simply by having a patient spit into a test tube and testing that sample.

To perform a genetic test, scientists take this sample and screen the DNA for mutated sequences, which can indicate any of a number of things, including an increased risk for developing a disease, sensitivity to bitterness, and susceptibility to addiction, to name a few.

When you receive your test results, youll likely want to consult with a genetic counselor on how to interpret them. A genetic counselor is a professional trained to help you appropriately respond and take action once you receive your results. A counselor can help you make important decisions about your health and the steps to take once you have your test results in hand.

Genetics and Your Family Tree

While genetic testing is most often used to uncover health information, it is becoming increasingly popular (and affordable) to learn more about your family tree by testing your DNA. This can range from paternity and maternity testing (to discover your biological parents identities) to tracing back your ancestral heritage tens of thousands of years. If you want to learn about your ancestry but are wary about learning about your genetic disease risk, some companies offer genetic test that will simply test for heritage.

Genetics, Your Health and Your Future

As you may already know, a genetic test result that comes back positive for a mutation does’nt mean that you’ll necessarily develop the specific disease in question. In fact, such information may help you avoid experiencing the disease should you take necessary precautions and develop a customized health plan with your doctor.

If you have a family history of a genetic disease, you may opt to have a test done to determine your risk. Some common diseases that have genetic links include:

  • cancer
  • diabetes
  • heart disease
  • mental illnesses (anxiety disorders, ADHD, eating disorders)
  • neurological disorders, (such as Alzheimer’s disease, Lou Gehrig’s disease, and MS).

Once you’ve determined your risk for particular genetic disease, you can work with your doctor and your genetic counselor to create a customized health plan. For example, if you discover that you’re at increased risk for developing breast cancer, you can opt for annual mammograms, perform more frequent self-checks, and educate yourself on the early signs of breast cancer. While most genetic diseases can’t be prevented, they can often be treated, managed and even cured if caught early.

Genetic Testing Drawbacks and What You Can’t Learn

Its important not to put too much faith in your test results. Genetic testing isnt a crystal ball, nor does it take the place of a doctors advice or diagnosis. There are common misconceptions about what a test can tell you. Genetic testing cannot predict with certainty:

  • what your absolute risk is for developing a disease (percentages)
  • whether or not you will inherit a certain genetic disease
  • whether or not your future children will inherit a certain genetic disease.

Because it is non-invasive, genetic testing poses few health risks and for many, is an excellent tool to use to achieve optimal health. However, there are ethical considerations to take into account when considering genetic testing in most forms. Ethical considerations that arise as a result of genetic testing include:

  • If you are at increased risk for developing a fatal genetic disease, your family may share that high risk. Will you tell your family members about your increased risk of a life-threatening condition? Should they know that they, too, may be at high risk? What if they don’t want to know about their disease risk?
  • If you are having an embryo tested for genetic disease, what are your feelings on terminating a pregnancy? At what point do you believe that human life begins? What are your thoughts on raising a child with a debilitating or fatal genetic disease or disability?
  • If you discover you or your partner are carriers for a genetic disease, your child will have an increased risk of developing that disease. How does this inform your decision to start a family?

Resources

Franklin, D. (2009). Family struggles with ambiguity of genetic testing. Retrieved July 7, 2009, from the National Public Radio Web site: http://www.npr.org/templates/story/story.php?storyId=98818197.

Human Genome Project staff. (2008). Human genome project information: Gene testing. Retrieved June 6, 2009, from the Human Genome Project Web site: http://www.ornl.gov/sci/techresources/Human_Genome/medicine/genetest.shtml.

Library Index staff. (2009). Genetics and health: Common genetically inherited diseases. Retrieved July 7, 2009, from the Library Index Web site: http://www.libraryindex.com/pages/2972/Genetics-Health-COMMON-GENETICALLY-INHERITED-DISEASES.html.

National Institutes of Health Web site (n.d.) Genetic testing. Retrieved July 6, 2009, from the Medline Plus Web site: http://www.nlm.nih.gov/medlineplus/genetictesting.html.

Pathway Genomics staff. (2008). Genetic testing: How it works. Retrieved July 6, 2009, from the Pathway Genomics Web site: http://www.pathway.com/how_it_works.