Spotlight on Neurogenetics

Beverly Yashar
Program Director, Genetic Counseling Program
M.S., genetic counseling, University of Michigan
Ph.D., genetics, University of North Carolina

Genetic counseling offers information and perspective

As new information accumulates about genes and disease risk, the work of genetic counselors becomes both more rewarding and more challenging. On one hand, access to the ever-expanding trove of information on heritable disorders can help patients and their physicians make better-informed decisions and provide new insights into the management of certain diseases. At the same time, the picture emerging from research is one of complex interactions among genes, genetic modifiers and environment – a tangle that is anything but easy to interpret. Helping patients make sense of it all is the genetic counselor's daunting task. The profession is up to the challenge, says Beverly Yashar.

"We're used to dealing with gray areas," she says. "Sometimes people have the idea that genetics can answer everything – that when you come to a genetic counselor we can give you a definitive answer that will tell you exactly what your future holds – if it's door A or door B. But that's a misconception. Genes give you a direction but do not determine absolutely what's going to happen."

Even with such a clear-cut condition as Huntington's disease, in which a single defective gene is sufficient to cause the progressive brain disorder, testing can reveal whether a person has the mutation and will definitely develop the disease, but not when symptoms will begin and how quickly it will progress.

With other conditions, the crystal ball is even murkier. "We know environment affects the start and progression of disease, and we know there are gene-gene interactions and modifications of genes that occur, but we don't have a formula where we can plug in gene 1, plus gene 2, plus gene 3 and throw in a little bit of cigarette smoking and ba-boom, there's your answer," says Yashar. "I doubt we'll ever be able to offer absolutes – that's not the nature of genomic medicine. But I think the day is coming when we'll have a better handle on how to put together that complex algorithm and perform risk calculations that will give our patients a clearer picture of their health and suggest ways they can improve it."

Until that day, genetic counselors can not only provide the best available information on disease risk, but they can also prepare people to receive that information and help them put it in perspective.

Take the example of a person who has no symptoms of a disease but knows it runs in the family and wants to find out if he or she will develop the condition. A genetic counselor can help the person decide if the time is right "to have that peek into the future," says Yashar.

After establishing -- through detailed conversation and a review of family members' test results -- that the disease indeed runs in the person's family, the counselor will explore with the person the likely impact of positive or negative results.

Someone who has seen family members affected by a hereditary disease usually has a pretty good idea how his or her own life will be affected by developing the disease. "But it's equally important to think about the implications of a good outcome," Yashar says. "One of the things we do is preview that by asking, 'What will it feel like if you test negative?' On one level they may think it's great, but they're still part of a family where there are other members who are positive, so we ask them to think about how they will have conversations with other family members."

In that way, genetic counseling spans the seemingly disparate realms of scientific fact and human emotion. "On the genetic side, we're armed with all the molecular medical information one needs to understand to make an informed decision about whether or not to have genetic testing and what the results mean," says Yashar. "On the counseling side, we're prepared to explore with people the implications for their personal well-being and their relationship to the family as a whole."