Genetic Carrier Testing
In the past, people did not discover that they were a carrier for an inherited genetic disease until after they gave birth to a child with that disease. The Center for Medical Genetics offers Generation® Genetic Carrier Screening that can help you understand your chances of delivering a child with an inherited disease — even before you get pregnant.
What is a genetic disease?
A genetic disease or disorder is the result of changes, or mutations, in an individual’s DNA. Genetic diseases can be inherited because of mutations in the cells involved in passing genetic information from parents to offspring.
What are genes?
Individual genes are formed from patterns of DNA. These are the instructions located in our cells that direct how our bodies grow and develop. Genes come in pairs — one copy from your mother and one copy from your father. One gene might be normal and the other might have a mutation. In most cases, you would be healthy, but also a carrier of the genetic mutation. If both copies of the gene are affected, you would likely show disease symptoms. DNA tests can help you know what’s in store.
How does my family history play a role?
A particular disorder might be “running in a family” if more than one or more relatives have the condition. The genetic conditions might be caused by mutation of a single gene. Other conditions that appear to run in families are caused by environmental factors such as dietary habits or a combination of genetic and environmental factor. Examining the family history in conjunction with genetics testing can help determine whether a family condition is inherited. Members of certain ethnic groups (e.g. Ashkenazi Jewish, African-American, Southeast Asian, etc.) may also have an increased chance to carry specific genetic disorders, regardless of family history.
What are the most common genetically inherited diseases we off carrier testing for?
- Cystic Fibrosis testing
- Duchenne/Becker Muscular Dystrophy testing
- Sickle Cell Anemia testing
- Thalassemias testing
- Fragile X Syndrome testing
- Spinal Muscular Atrophy testing
How can genetic testing determine my chances of having a child with a disorder?
A genetics professional can identify the genetic makeup of each parent and use those factors to determine the likelihood of the disorder. For example, if two unaffected parents each carry one copy of the mutated gene for an autosomal recessive disorder, their child has a 25 percent chance of having a child with the disorder. Cystic fibrosis and sickle cell anemia are examples of autosomal recessive disorders.
What kind of test is given?
Recent advances in genetics science have resulted in tests that can screen for a broad range of genetic diseases. A simple blood test is given. Results take around two weeks. You can take the test at any time, ideally before you become pregnant.
What happens after the test?
A genetics counselor will discuss the results and your degree of risk after the genetic testing. Depending on the degree of risk, you may consider other reproductive options, including egg and sperm donors, prenatal diagnosis, adoption, or early preparation in advance of the birth.
Where can I learn more about specific genetic conditions?
The National Institute of Health offers a Guide to Understanding Genetic Conditions
For information about our other prenatal services, please click here for the Center for Medical Genetics website.