Understanding Genetic Carrier Screening: What You Need to Know

Highlights

• Genetic carrier screening is a test that can be done either by a mouth swab or blood test.
• The test looks for mutations (changes or mistakes) in your genes that could cause a health problem for your baby.
• There are different types of tests that look for different health conditions.
• Make sure that you ask your doctor how much carrier screening will cost you.

In This Article

• Carrier Status Screening
• Who is a Genetic Carrier?
• Types of Carrier Screening
• Carrier Status Screening Recommendations
• Is Genetic Carrier Screening Right for Me?
• Arranging Genetic Carrier Screening
• Cost of Genetic Carrier Screening
• After the Screening
• Frequency of the Test
• Tools And Assistance

Carrier Status Screening

Carrier status screening is a genetic test that identifies whether you carry genes for specific inherited health conditions. The test can be done through a blood sample or a saliva swab, and it can help determine your risk of passing on genetic conditions to your children. By understanding whether you carry genetic mutations, you can make more informed decisions about family planning and reproductive options.

The results of carrier screening allow individuals and couples to explore different options, such as using in vitro fertilization (IVF) to conceive or undergoing diagnostic testing during pregnancy to assess the health of the baby. Carrier screening is not intended to diagnose a condition, but rather to provide valuable information about your genetic makeup and the potential risks for your offspring.

Who is a Genetic Carrier?

A genetic carrier is a person who carries one copy of a faulty gene for a specific inherited condition but does not display symptoms of that condition. Humans inherit two copies of each gene, one from each parent. If one of these copies contains a mutation or faulty version of the gene, the person is considered a carrier. Carriers do not usually experience the health problems associated with the condition because they have one normal copy of the gene that compensates for the faulty one.

While carriers do not experience the effects of the condition, they can pass the faulty gene on to their children. If both parents are carriers of the same genetic condition, there is a 25% chance with each pregnancy that the child will inherit two faulty copies of the gene (one from each parent) and develop the condition. There is a 50% chance the child will inherit one faulty gene and become a carrier, and a 25% chance the child will inherit two healthy copies of the gene and not be affected by the condition.

Types of Carrier Screening

There are several types of carrier screening tests available, depending on the conditions you are being tested for. These tests vary in the number of conditions they screen for and the complexity of the testing process:

Single Condition Screening

This test focuses on detecting one specific genetic condition. It is usually chosen if there is a known family history of a particular genetic disorder.

Multi-Condition Screening

Some tests screen for a small number of genetic conditions, often including cystic fibrosis (CF), spinal muscular atrophy (SMA), and fragile X syndrome (FXS). These conditions are relatively common and are typically included in basic multi-condition tests.

Expanded Carrier Screening

Expanded carrier screening tests for hundreds of inherited conditions, providing a broader overview of the potential genetic risks. This approach is becoming more popular as it helps individuals and couples assess a wider range of genetic conditions that could affect their future children. It is particularly useful for those with no known family history of genetic disorders, as it can reveal carrier status for conditions that may not have been previously considered.

Carrier Status Screening Recommendations

Carrier status screening is often recommended for people planning to start a family, as it helps assess the risk of passing on genetic conditions to future children. It can also be offered to individuals in the early stages of pregnancy, particularly if there are concerns about a family history of certain inherited conditions.

The decision to undergo carrier screening is typically made in consultation with a healthcare provider. Some people may choose to undergo testing as a precaution, while others may opt out, especially if they feel the results may not change their reproductive plans.

Screening is especially beneficial if you or your partner have a known family history of genetic conditions or if you belong to an ethnic group that is known to have a higher risk for certain genetic disorders. A healthcare provider can help assess whether carrier screening is appropriate based on individual factors such as family history and ethnicity.

Is Genetic Carrier Screening Right for Me?

Genetic carrier screening is not a mandatory test, and whether or not it is right for you depends on your personal circumstances. There are many different genetic conditions caused by mutations in specific genes, and it is rare for both parents to be carriers of the same condition. However, carrier screening provides important information about the likelihood of having a child with a genetic disorder, which can be particularly helpful in making informed decisions.

It is important to note that genetic carrier screening does not detect all possible genetic conditions. Even if both partners undergo testing and receive negative results, it does not guarantee that a child will be free of genetic issues. Carrier screening is just one part of the reproductive decision-making process, and it does not replace other prenatal tests that can be done during pregnancy, such as non-invasive prenatal testing (NIPT) or amniocentesis.

Before making the decision to undergo genetic carrier screening, it is important to discuss the pros and cons with a healthcare provider. The results can provide reassurance, but they can also raise difficult questions. Ultimately, the decision to undergo screening should be based on individual preferences and the information available to make an informed choice.

Arranging Genetic Carrier Screening

Genetic carrier screening can be arranged by a healthcare provider, such as a doctor, obstetrician, or genetic counselor. The healthcare provider will assess your personal and family medical history, and if they believe carrier screening is appropriate, they will provide a referral for the test. You will then visit a pathology collection center to have a blood sample taken or a saliva swab performed.

It is important to inform your healthcare provider if you have a family history of genetic disorders, as this may influence which conditions are tested for. The genetic testing will be performed in a specialized laboratory, and the results will typically be available within 2 to 4 weeks.

Cost of Genetic Carrier Screening

The cost of genetic carrier screening varies depending on the test selected and the provider. Single-condition screenings tend to be less expensive, while expanded carrier screening can be more costly due to the larger number of conditions tested. The price of genetic testing can range from a few hundred dollars to over a thousand dollars, depending on the extent of the screening.

In some cases, health insurance may cover part of the cost, particularly if there is a family history of certain genetic conditions. It is important to check with your insurance provider and the testing laboratory to understand what costs will be covered.

Many people who undergo carrier screening may be eligible for partial reimbursement or financial assistance through public health programs, depending on their specific situation. It is advisable to discuss the cost and payment options with your healthcare provider before proceeding with the test.

After the Screening

Once your carrier screening results are available, your healthcare provider will discuss the findings with you. If the results show that you are a carrier for a specific condition, you may be referred to a genetic counselor for further advice and support. Genetic counselors can help you understand the implications of your carrier status and provide guidance on the next steps.

If both you and your partner are carriers of the same condition, you may consider additional options, such as:

• Preimplantation genetic testing (PGT) with IVF
• Prenatal diagnostic testing, such as chorionic villus sampling (CVS) or amniocentesis

If you are already pregnant, genetic testing results may lead to further prenatal tests to assess the health of your baby. It is important to understand that a positive carrier screening result does not mean your child will definitely have the condition, but it may warrant further investigation to understand the risk.

Frequency of the Test

Genetic carrier screening is typically done once in a lifetime. Once you and your partner have been tested and the results are known, you do not need to repeat the test for subsequent pregnancies, unless you have a new partner. If you are a carrier and enter into a new relationship, it is recommended that your new partner undergo carrier screening to assess the potential risks for future children.

Tools And Assistance

• Genetic Counseling: A professional genetic counselor can provide guidance and support after receiving carrier screening results. They can help explain the results, discuss the implications, and recommend possible next steps, such as additional testing or reproductive options.
• Carrier Screening Tests: Several types of carrier screening tests are available, including single condition, multi-condition, and expanded carrier screening. Depending on your personal and family medical history, a healthcare provider can recommend the most appropriate test.
• Financial Assistance: Many individuals may qualify for financial assistance or reimbursement through public health programs or insurance coverage, depending on the specifics of their situation. Be sure to discuss financial options with your healthcare provider before undergoing testing.

Need more information?

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