Used at the right time and for the right reasons, genetic testing can be a powerful addition to your care provider’s toolkit. It is important to discuss this information with your healthcare provider or a genetic counselor if you are interested in pursuing genetic testing.
Capabilities of Genetic Testing and Screening
There are several different types of genetic tests. Genetic testing is typically performed on a blood sample or saliva sample.
- Diagnostic testing is a type of testing that is used to determine if someone has a genetic condition. It may be used to confirm a clinical diagnosis if a genetic condition is suspected.
- Predictive testing is a type of testing that can be used to help predict the future risk of developing a disease in a person who is asymptomatic or has not developed a certain disease. For example, predictive testing can be used to determine if someone has a hereditary cancer syndrome may cause an increased risk to develop certain types of cancer. A common example is BRCA1 and BRCA2 testing based on a family history of breast or ovarian cancer.
- Carrier screening is a type of genetic screening that can be offered to individuals who are currently pregnant or planning a pregnancy. It can tell you whether you carry a gene for certain genetic disorders. If a particular condition like cystic fibrosis has occurred in your family, genetic screening can tell you whether you carry the gene mutation as you consider having children.
- Prenatal screening can be performed during a pregnancy using maternal blood and/or ultrasound to identify pregnancies that may have a higher risk for a chromosomal or genetic disorder.
- Prenatal testing is diagnostic, invasive testing that can be performed during pregnancy to determine if the fetus has a specific genetic condition or a chromosomal disorder. This is typically performed by an amniocentesis or chorionic villus sampling (CVS). It is important to know that prenatal testing does not identify all genetic conditions or birth defects.
- Newborn screening is performed on newborns soon after birth, typically within 1-2 days at the hospital. It screens the baby for many rare but serious medical conditions, allowing doctors to begin treatment promptly if necessary.
- Medication efficacy testing, also known as pharmacogenomic testing, provides healthcare providers with information that they can use to help determine what medication and at what dose will be most effective in treating a person’s disease.
Possible Risks and Limitations of Genetic Testing
- Lack of conclusiveness: Testing positive for a particular condition does not guarantee the condition will develop. Similarly, a negative result does not guarantee that you will not develop a particular disease.
- Physical risk: There is typically little physical risk associated with genetic testing that is performed by blood draw or cheek swab. However, prenatal testing such as amniocentesis or chorionic villus sampling does carry a small risk of pregnancy loss, or miscarriage.
- Emotional distress: You may find yourself feeling anxious, depressed or guilty following genetic testing. It can reveal some conditions for which there is no effective treatment, which could cause someone to feel sad or hopeless.
- Genetic Discrimination: In the United States, the federal Genetic Information Nondiscrimination Act of 2008 (GINA) helps prevent health insurers or employers from discriminating against someone based on genetic test results. However, GINA does not cover life, long-term care or disability insurance.