Why do I want to know?
If you have or your child already has symptoms of a condition that might be genetic, testing may contribute to a diagnosis or treatment. Genetic testing also can help with planning for the future, including whether to have children.

Is a specific genetic therapy or treatment available?
“If no treatment is available, would you still want to know?” asks Lenika De Simone, a genetic counselor at the Ann & Robert H. Lurie Children's Hospital of Chicago. “Some people may not want to find out, but for others, just having an answer is positive.”

How will this information affect the rest of my family?
“Genetic testing results can affect multiple generations of family members,” says Lola Cook, a genetic counselor at the Indiana School of Medicine in Indianapolis. That was the case for Holly Roos, whose two children were diagnosed with fragile X syndrome, an inherited disorder that causes intellectual disabilities. Her genetic counselor advised her to encourage other family members to get tested. After speaking to cousins, aunts, and uncles on both sides of her family and urging them to get tested, Roos and the counselor were able to trace the fragile X mutation back five generations on her father's side. “We reached out to the family members who carried the mutation and encouraged them to talk to doctors and genetic counselors who could help them understand their risk not only for passing on the gene but for developing fragile X–related disorders themselves.”

Should I see a genetic counselor?
“I very much encourage this,” says Anna Szekely, MD, an attending physician in the neurogenetics program at the Yale School of Medicine in New Haven, CT. “A discussion helps you explore and make sense of the possibilities.” A session with a counselor can be empowering, agrees Cook. “Keep in mind, also, that discoveries are being made rapidly in the genetics of neurologic disease. Having a relationship with a genetic counselor can help you understand new developments.”

How do I choose a counselor?
Look for someone with experience in the disorder you're concerned about, advises Roos. “Getting genetic counseling from someone with the right expertise helped me understand how my children would learn,” she says. “It also helped me manage my depression and anxiety about being a carrier of the mutation and gave me hope about advances in research.” The National Society of Genetic Counselors offers an online directory of counselors that allows you to filter by specialty, including neurogenetics, and to select an in-person or telehealth appointment. You also can ask your family doctor or neurologist for a referral to a genetic counselor or a neurogeneticist.

What else can I do with the information I receive from testing?
You may want to participate in a clinical trial for a new therapy. Testing also might avoid unnecessary medical care. “Genetic testing that identifies a disorder that runs in your family may help avoid a nonproductive search for other causes of symptoms, including costly and possibly unnecessary tests,” says Brent Fogel, MD, PhD, FAAN, director of the UCLA Clinical Neurogenomics Research Center.

What are the downsides?
“People worry that a genetic diagnosis may affect their ability to get or keep health insurance,” says Dr. Szekely. “The Genetic Information Nondiscrimination Act (GINA) prohibits discrimination on the basis of genetic information in employment or health insurance, but it does have some limitations.” GINA exempts businesses with fewer than 15 employees, and it doesn't apply to people who receive insurance through the federal government or the military. Test results could end up being inconclusive—or unhelpful. “If you get a testing panel for a set of genes that cause neuropathy, for example, and the test comes back negative, all that means is that you don't have any of the identified mutations in the genes that are on that panel. It doesn't mean you don't have a mutation in a gene that wasn't tested,” says Dr. Fogel. “On the other hand, if the test finds a rare variant in one of those genes, suddenly that may seem significant but might not be the answer.”

What can I expect as far as cost and other factors?
Testing ranges from a few hundred to several thousand dollars and may not be covered by health insurance. “If the genetic experts say you don't need a particular test, that doesn't mean you're not getting proper care,” Dr. Fogel says. “Make sure to ask questions. There are many reasons why a particular test may or may not be appropriate for you, and a knowledgeable physician or genetic counselor will be able to explain that to you.”

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