In many instances, surprises can be a good thing — a surprise birthday party or a surprise vacation, etc. One place where surprises are rarely welcomed is when it comes to our health. While many of us can fall back on family medical history, sometimes that’s not an option. Other times, family history may give you a vague idea of what diseases or conditions can run in your family, but not the specifics. This is where genetic testing comes in.
What is Genetic Testing?
Genetic testing is a medical analysis of your DNA, the hereditary material that defines the makeup of living organisms. The organization of your DNA isn’t just what organizes you as a human, it can also pinpoint even more personal details. A doctor will take a sample of your DNA and analyze it to get an idea of your genetic health and chances of developing hereditary diseases or cancers.
Genetic testing is a medical analysis of your DNA that can be used for diagnosis or predictive or pre-symptomatic medicine.
The type of sample taken depends on the type of test. Two of the most common samples taken are blood or cheek cells. Samples can also be taken from amniotic fluid (amniocentesis) or the placenta (choronic villus sampling). Once a sample is taken, it’s sent off to a lab for analysis. You’ll then meet with your doctor for the results.
These results may not diagnose illnesses, but they can be used to predict the potential for certain diseases or conditions. If you’re concerned that these results may preclude you from certain coverage or cause job discrimination, don’t worry! The Genetic Information Nondiscrimination Act of 2008 (GINA) prevents discrimination based on the results of a genetic test.
Why Would You Want to Get It?
There are many reasons why you would want to participate in genetic testing.
To Confirm or Treat Disease
A very common reason you’d order testing would be for diagnostic purposes. Some genetic diseases caused by mutations can be confirmed by testing. This is an important diagnostic step, if your doctor suspects you have a specific condition. This method is also effective for pharmacogenetics, which uses genetic testing to help identify effective drug treatments and dosages, specific to your makeup.
To Predict Your Chances of Having a Disease or Carrying the Gene
As mentioned above, family health history is another reason you may want to participate in genetic testing. This is called predictive or pre-symptomatic genetic testing. This examination looks at your genes for changes that may point to your chances of developing specific illnesses. While it’s not a 100 percent guarantee that you’ll end up getting these diseases, it can alert you to illnesses you should watch for, like prostate cancer in men. This also makes it effective for carrier testing to identify if you have the gene linked to specific diseases like sickle cell anemia or cystic fibrosis. This is most often tested by expecting parents or those who plan to become parents, to see if they’ll pass on specific genes to their children.
Pregnancy and Childbirth
This gets us to the other major reason why people get genetic testing — they’re pregnant, planning to be pregnant, or have given birth. Along with the aforementioned carrier testing, some expecting parents will have prenatal testing done, which can detect some abnormalities in a baby’s genes. This is usually conducted via a blood test or amniocentesis. A newer method called, cell-free DNA testing, uses the mother’s blood to analyze the baby’s DNA.
The most common type of genetic testing is a newborn screening, which is required to be performed in the United States.
Preimplantation testing is a type of genetic test that can be used when parents hope to become pregnant through in vitro fertilization and wish to check for genetic abnormalities. Finally, the most common type of genetic testing is a newborn screening, which is required to be performed on babies in the United States. This test is essential, because it can check for abnormalities and enable immediate treatment if necessary.
Understanding the Results
Your doctor will most likely deliver the genetic test results directly to you. This will allow him/her to explain and expand on what the results mean for you. The results will come back as positive, negative, or inconclusive. A positive result means that your test results showed you carry the gene or genetic mutation specified. If this test was taken for a diagnostic reason, the results should confirm that you have the condition. This will allow your doctor to come up with a treatment and a plan moving forward. If the test was taken for predictive or carrier status reasons, these results usually won’t mean that you will definitely develop the illness or disease. Instead, the gene means you’d be at a heightened risk of the disease. Only in specific cases, like Huntington’s disease, does having the gene mean you’ll eventually develop it.
A positive result usually won’t mean that you’ll definitely develop the illness or disease, just that you’re at a heightened risk to.
If you receive negative results, this means that you don’t appear to have the genes that were being tested for. While this is a good sign, it doesn’t mean that you don’t have or won’t develop the condition in the future. It simply means that you’re not at a heightened risk to carry this gene. For example, if you don’t have the BRCA breast cancer gene, you may still develop breast cancer at some point. An inconclusive or uncertain result means that your doctor wasn’t able to glean helpful information from the test. In these instances, a doctor may ask you to retake the test, test other family members, or plan for regular checkups to monitor the condition more closely.
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Ultimately, a genetic test can be an enlightening scan that influences your general health, lifestyle, and medical choices. At the same time, these tests can be essential if you’re planning to have a family, since your genetics can become a part of your child’s genetic makeup. While they may not always confirm that you will develop or pass on an illness, genetic testing can help you focus on diseases you’re more likely to contract or carry, so you can plan or catch them early.