Carrier Screening: Frequently Asked Questions

What is carrier screening?

Carrier screening is a genetic test determining if a person is a carrier for a specific genetic condition. It can be done before or during pregnancy to identify if the parents are carriers of a genetic condition that could be passed on to their child.

What is a recessive disorder?

Most carrier screening is for recessive disorders. A recessive disorder is a genetic condition that requires two copies of an abnormal gene —one inherited from the mother and one inherited from the father— to be present for the disorder to develop. If only one copy of the abnormal gene is present, the individual is typically a carrier for the disorder but does not show any symptoms. When two carriers of a recessive disorder have a child, there is a 25% chance that the child will inherit two copies of the abnormal gene and develop the disorder.

What are the chances of having a child with a recessive disorder?

The chances of having a child with a recessive disorder depend on a number of factors, including whether or not both parents are carriers of the same disorder. If both parents are carriers for a particular recessive disorder, there is a 25% chance with each pregnancy that their child will inherit two copies of the abnormal gene and develop the disorder. If only one parent is a carrier, the child will not have the disorder, but there is a 50% chance that the child will be a carrier like the parent.

Who should consider carrier screening?

Carrier screening is typically recommended for individuals and couples who are planning to have a child or who are already pregnant and are at increased risk for certain genetic conditions due to their family history or ethnicity. It is also often recommended for people who have a child with a genetic disorder or for couples who have experienced multiple miscarriages or stillbirths.

How do I decide which patients to offer carrier screening to? 

Carrier screening is typically recommended for all individuals planning to have a child, but may also be useful for patients with a family history of genetic disorders or certain ethnic backgrounds at higher risk for certain disorders.

What type of informed consent is required for carrier screening?

Informed consent for carrier screening typically involves explaining the purpose of the test, the possible results, and the implications for family planning. Patients should have the opportunity to ask questions and make an informed decision about whether or not to proceed with testing.

What are the benefits of doing a carrier screen test?

The benefits of carrier screening include the ability to identify individuals who carry a gene for a certain inherited condition, and the ability to make informed decisions about family planning. Carrier screening can also help identify individuals who are at higher risk for certain genetic conditions, so that they can take steps to manage that risk. For example, if a couple is found to be carriers of a genetic condition, they may choose to pursue prenatal testing or in-vitro fertilization with preimplantation genetic diagnosis (PGD) to avoid passing the condition on to their child. Additionally, carrier screening can also help identify individuals who may be at higher risk for certain health conditions, such as certain types of cancer, so that they can take steps to manage that risk.

How is the carrier screen test done?

The test is usually done by taking a blood sample or a saliva sample. The sample is then analyzed in a laboratory to look for any genetic mutations that could indicate a risk for certain inherited conditions. To simplify the sampling process, Galenvs carrier screen test is done from a simple saliva sample.

What are the results, and what do they mean?

Results from the carrier screening test can be either positive or negative. A positive result means that you carry a gene for a certain inherited condition, while a negative result means that you do not carry the gene for that condition. It’s important to note that a positive result does not mean that you or your child will develop the condition but rather that there is a risk that the condition could be passed on to future children.

What should I do if my test results are positive?

If your test results are positive, it’s important to discuss the results with a genetic counselor or a healthcare professional who is trained in genetic medicine. They can help you understand your results, the potential risks to your child, and any options that may be available for managing the risk, such as prenatal testing or genetic counseling.

What is the accuracy of carrier screening?

The accuracy of carrier screening depends on the specific condition being tested. Some genetic conditions have a high carrier rate and are therefore easier to detect. Other conditions have a low carrier rate and may be more difficult to detect through carrier screening. In general, carrier screening is highly accurate, but it is not a perfect test and cannot detect all genetic conditions.

What should I do if I am a carrier for a genetic condition?

If you are a carrier for a genetic condition, it does not mean that you will develop the condition or that you will pass it on to your children. However, it does mean that you may be at increased risk of having a child with the condition. You should discuss your test results with a genetic counselor or healthcare provider to understand your options and the risks involved.

 What genetic disorders are screened for in a carrier screening test?

The specific genetic disorders screened for may vary depending on the test, but some of the most common ones include cystic fibrosis, sickle cell anemia, Tay-Sachs disease, and spinal muscular atrophy.

Can carrier screening be done during pregnancy?

Yes, carrier screening can be done during pregnancy. Prenatal testing options include chorionic villus sampling (CVS) and amniocentesis. These tests can be done during the first or second trimester of pregnancy and can identify if the developing baby has a genetic condition. However, these tests carry a small risk of miscarriage and are usually only recommended for people who are at increased risk for genetic conditions or who have had abnormal results on other prenatal screenings.

How long does it take to get the results of a carrier screening test?

The turnaround time for results can vary depending on the specific test and the lab processing it. At Galenvs, we offer a 1 week turnaround time from the moment we receive your saliva sample.

What are the limitations of a carrier screening test?

Carrier screening tests only screen for a limited number of genetic disorders, and there may be other disorders that are not detected. Additionally, the test results do not provide a definitive diagnosis for a genetic disorder and should be interpreted in the context of other clinical and family history information.

Does insurance cover carrier screening?

Carrier screening is usually covered by insurance, but coverage can vary depending on the specific test and the insurance plan. It is a good idea to check with your insurance provider to understand what is covered and what out-of-pocket costs you may be responsible for.

Where can I get carrier screening?

Carrier screening is available through healthcare providers, genetic counseling clinics, and specialty laboratories. You can also discuss carrier screening options with your obstetrician or primary care doctor.