For many patients, a genetic test (DNA test) is essential for diagnosing a genetic disorder. There are three common types of genetic disorders:
- Single-gene disorders (e.g., sickle cell anemia) are caused by mutations in just one gene.
- Chromosomal disorders (e.g., Down syndrome) are due to having certain chromosomes missing, extra or with structural changes.
- Complex disorders (e.g., hereditary colon cancer) can result from one or more genes with a mutation plus the effects of lifestyle and environment.
Different kinds of genetic tests
- Diagnostic testing: In many cases, the right diagnostic test can definitively identify or rule out a genetic condition. These tests can be performed prior to birth as part of prenatal testing (e.g., amniocentesis) or at any point during your life. There is a not a test for every genetic condition, and some conditions have more than one test. Your genetics specialist will help guide you to the best plan for you.
Carrier testing: This kind of testing can be offered to people with a family history of a genetic disorder or as general screening in planning a pregnancy. It is also offered to people in certain ethnic groups that have increased risks of genetic issues that can lead to certain diseases:
- Cystic fibrosis
- Sickle cell disease (sickle cell anemia)
- Thalassemia disease
- Tay Sachs disease
- Newborn screening: The Illinois Newborn Screen includes over 50 different conditions that can be life-threatening for a newborn. With a simple blood spot test, the newborn screen identifies conditions such as phenylketonuria (PKU) and congenital hypothryroidism that require regular treatment. By diagnosing these babies shortly after birth, we can dramatically improve their long term outcome.
- Predictive and presymptomatic testing: These tests can be helpful if you have no symptoms of a disease but have a family member with a genetic disorder. This kind of test can be used to determine your risk of developing some kinds of cancer (e.g., certain types of colon cancer [FAP], breast cancer and ovarian cancer) as well as many other conditions, including neurological, cardiac and connective tissue disorders.
- Preimplantation testing (PGD): These tests are performed on embryos created through in vitro fertilization (IVF). Families can opt to use only embryos that do not have mutations to reduce the risk of having a baby with a particular genetic disorder.
Is genetic testing right for you?
The decision to undergo a genetic test is extremely personal and should be based on your family history and discussions with your doctor. Genetic tests can be performed for a variety of reasons and can do the following:
- Accurately diagnose a person who has symptoms of a genetic disease
- Reveal genetic diseases in adults and children before they cause any symptoms, allowing preventive maintenance and care
- Help doctors decide the best course of treatment for a specific genetic disease
- Identify a genetic disease in a pregnancy
- Determine if parents might be gene carriers for a disease that they might affect their children
Genetic specialists at Rush are available to help you explore your options.
What is a genetic counselor and how can they help?
Undergoing genetic tests, for whatever reason, can be extremely stressful and confusing. Genetic counselors at Rush have been trained to do the following:
- Assess your family history
- Explain genetics concepts relevant to you
- Discuss and help you make decisions about testing options
- Explain genetic test results
- Help you coordinate with your family if necessary
- Help you explore treatment options if needed
Why choose Rush for genetic testing
- At the genetic disorders program at Rush, genetic specialists use diagnostic genetic tests to best care for prenatal, pediatric and adult patients. Genetic counselors help you navigate the tests, results, and next steps.
- The Fetal and Neonatal Medicine Program at Rush brings together multiple specialists, including genetic counselors, to meet with expectant families who have concerns about their unborn baby’s health. They provide medical expertise as well as map out treatment plan for pregnant women and their babies. They also offer valuable second opinions so you can make the most informed decisions possible.
- The Sandra Rosenberg Registry for Hereditary and Familial Colon Cancer at Rush helps identify people at risk for inherited forms of colon cancer. The registry provides both support and care as families navigate the diagnostic and treatment process. It is the only active registry of its kind in Illinois and one of just 32 in the United States.
- The Rush Inherited Susceptibility to Cancer (RISC) Program counsels people on their personal and family risks for developing cancer. Physicians check women for genetic mutations (BRCA1 and BRCA2) associated with breast cancer and ovarian cancer using a simple blood test.