Some unaffected people want to know if they are at risk for ALS, while others would prefer not to know. Consultation with a genetic counselor can help you decide if testing is the right decision for you. Testing is most useful in a person who has been diagnosed with ALS.
To Test or Not To Test
People living with ALS may choose to undergo genetic testing, while others may not.
- Some reasons people at-risk for familial ALS decide to have testing include:
- Some reasons people at-risk for familial ALS decline genetic testing include:
- Getting more information to help make life decisions
- Allowing time to adjust to the fact they will likely get ALS
- Reducing anxiety
- To help guide reproductive decisions
- To provide information for the next generation.
- The desire to avoid worry about getting ALS
- Knowing there is currently no cure
- Avoiding guilt about passing it on to children or testing negative when others in the family test positive.
If there is more than one person with ALS and/or frontotemporal dementia [LINK to FTD page] in your family or someone was diagnosed at a younger age (such as age 45)[JY2] , you may want to meet with a genetic counselor.
- Meeting with a genetic counselor involves taking a detailed medical and family history, evaluating risks, and discussing the impact of genetic testing.
- A genetic counselor can help you work through the pros and cons of genetic testing based on your concerns and values. Genetic counseling does not always lead to genetic testing.
- For more information about genetic counseling or how to find a counselor in your area, please visit the National Society of Genetic Counselors webpage: www.nsgc.org.
Genetic Testing Information
Genetic testing is a type of medical test that identifies changes in a person’s chromosomes, genes, or proteins. The results of a genetic test can confirm or rule out a suspected genetic condition, such as familial ALS. If a person is a gene mutation carrier, genetic testing can also help determine a person’s chance of developing or passing on a genetic disorder.
- Those families with familial ALS, where a mutation is not identified, may have familial ALS caused by a gene or genes that have not yet been discovered. Not having an identified genetic mutation does not eliminate a familial diagnosis and other family members may still be at risk for developing ALS.
- If a mutation has been identified, biological family members who don’t have symptoms can be tested to see if they inherited the genetic mutation; this is called predictive testing. Some medical centers may require a neurological exam, psychological assessment, and counseling before predictive testing.
- If a person in the family with ALS has a negative genetic test result (no identified genetic mutation), testing family members without a diagnosis of ALS will not provide more information. If no one in the family with ALS is available for genetic testing, a negative test result in an unaffected person cannot be interpreted.
How Does Genetic Testing Work?
- Genetic testing usually involves taking blood or spitting in a special type of tube. Because this testing needs to be ordered by a healthcare professional, the sample is usually taken in the doctor’s office or in a lab associated with the doctor’s office for evaluation.
- Results can take anywhere from a few weeks to a few months depending on the type of testing ordered.
- Results should be communicated by the genetic counselor or doctor who ordered the test. This is often done in person at a follow-up appointment or sometimes by telephone.
Genetic Testing Facts and Resources
Genetic testing may:
- Explain if there is a genetic cause of ALS in the family.
- Allow other family members to have testing to see if they carry the genetic mutation.
- Allow couples planning on having children to pursue prenatal testing.
Genetic testing does not:
- Currently change medical treatment.
- Diagnose ALS in people without symptoms.
- Tell a person without symptoms when they may start showing symptoms or what their progression will be.
- Because FALS is usually an adult-onset condition, genetic testing of children under age 18 is not recommended.
- Genetic testing protocols may differ among clinics. Some clinics may offer testing for different genes and focus on testing specific patients or people in a family. Other testing may be offered on a research basis only.
- Test results are not always straightforward. There are some genetic changes that scientists do not understand yet, so results can be difficult to interpret.
- Technology is changing rapidly and costs of testing are decreasing.
- More genes are being identified, so it may be useful to contact your genetic counselor periodically for updates.
- DNA banking is a valuable option for people with ALS who do not currently have an identifiable genetic mutation. DNA banking means storing a person’s blood so that it is available for future testing. For more information, you can consult a genetic counselor.
How Much Does Genetic Testing Cost?
- Genetic testing for all of the currently known FALS genes can cost from about $1600 to $5000. Genetic testing for one gene usually costs $500 - $1500[JY3] . When the genetic mutation in a family is already known, the cost to test for the familial mutation is usually around $400.[JY4]
- Genetic testing is not always covered by insurance. Check with your insurance company about any out of pocket expense prior to testing.
Could Genetic Testing Lead to Problems with Employment or Insurance Discrimination?
- The Genetic Information Nondiscrimination Act of 2008 (also called GINA) is a federal law that protects people from genetic discrimination in health insurance and employment. Genetic information includes both a family history of ALS and a positive genetic test result. Please visit http://www.ginahelp.org for more information.
- GINA does NOT cover health insurance eligibility, premiums, or coverage for people who have already been diagnosed with ALS.
- GINA does NOT cover life insurance, long-term care, or disability. If you plan to have predictive testing, you should consider having these plans in place prior to testing.
For More Information
For more information or to find a genetic counselor near you, please visit the web-site for the National Society of Genetic Counselors www.nsgc.org.
The ALS Association thanks and acknowledges Deborah Hartzfeld, MS, CGC, Certified Genetic Counselor, for sharing her time and expertise on this factsheet. [INSERT PICTURE OF DEBORAH?]