You may choose to have genetic testing if you are concerned that you have an increased risk for having or getting a disease that has a genetic cause. The information you obtain from the tests may help you make decisions about your life. For example:
If tests show that you have an increased risk for passing on a disease to your child, you may choose to have more genetic testing while you are pregnant (prenatal testing). Or you may decide to adopt a child.
If tests show that you have an increased risk for developing a disease such as breast cancer, you may make decisions that help lower your risk of breast cancer.
You may feel reassured if the tests are normal.
You may decide to have a genetic test during pregnancy to find out whether your fetus has a disorder, such as Down syndrome. Information obtained from the test can help you decide how to manage your pregnancy.
Genetic testing can be used to find out the identity of a child's father (paternity). It can also be used in crime scene investigation.
What are the main types of genetic testing?
There are six main types of genetic testing:
Carrier identification determines whether people who have a family history of a specific disease or who are in a group that has an increased chance for that disease are likely to pass on that disease to their children. Information obtained from this type of testing can help guide a couple as they make decisions about pregnancy.
Prenatal testing determines whether a fetus has a disorder, such as Down syndrome. Information gained from this type of testing can help guide decisions about how to manage a pregnancy, including the decision about whether to end the pregnancy.
Newborn screening checks for various metabolic diseases, such as phenylketonuria (PKU). Information obtained from newborn screening can help guide medical treatment to ensure the best possible outcome for the baby.
Late-onset disease testing determines whether you carry a genetic change that increases your risk for developing a disease, such as breast cancer or Huntington's disease, later in life. This might be of interest if you have a relative who has the disease. Information from this type of testing can help you make decisions about preventing or managing the disease.
Genetic identification (DNA fingerprinting) can be used to determine paternity, help solve crimes, and identify a body.
Compatibility testing looks at genetic markers to see if an organ for transplant is suitable for a person who needs it.