Genetic Counseling For Usher Syndrome
June 27, 2014
by Katherine Lafferty, MS, CGC
If you ever want to have people stare at you blankly and quickly change the subject at a dinner party, simply answer, “I’m a genetic counselor” when asked, “So, what do you do?” Genetic counseling has been a profession since the early 1970’s and today there are thousands practicing worldwide. Yet many people have never heard of us. Of those who have heard of genetic counselors, some equate us to sci-fi films like Gattaca, wanting to create “designer babies,” or picture us as players in a new wave eugenics movement. Hopefully, in this brief time I can tell you a little about what genetic counseling really is. I provide the disclaimer that I cannot speak for every genetic counselor or every patient-genetic counselor interaction and I am slightly biased, being a genetic counselor myself. I hope that if you have already met with a genetic counselor, have avoided us like the plague, or are learning about genetic counselors for the first time, you will take this opportunity to learn more. In reading this article, you will understand our role in a healthcare team and hopefully find something that resonates with you in how we might be able to provide a service to you and/or your family.
The National Society of Genetic Counselors defines genetic counseling as the following:
“Genetic counseling is the process of helping people understand and adapt to the medical,psychological and familial implications of genetic contributions to disease. This process integrates:
- Interpretation of family and medical histories to assess the chance of disease occurrence or recurrence.
- Education about inheritance, testing, management, prevention, resources and research.
- Counseling to promote informed choices and adaptation to the risk or condition.”
Going off this definition, I can understand how many people contemplate the benefits of receiving genetic counseling for Usher syndrome. Some of the many questions I, and my colleagues, receive include:
- Why do I need genetic testing to tell me I have Usher syndrome, when I know I have Usher syndrome?
- Is the genetic counselor going to tell me I shouldn’t have any more kids?
- Why do I need to see a genetic counselor when I already saw the doctor?
- Is the genetic counselor going to make me talk about my feelings?
Before we go any further, let’s refresh with a little Genetics 101: Our chromosomes hold all of our genetic information and are the big instruction book for our bodies on how to grow, function, develop, etc. We have 46 chromosomes that come in pairs; one of each pair comes from our mom and the other of each pair we get from our dad. If you line up these chromosomes tall to small, they can be numbered 1 through 22 and the last pair, the sex chromosomes, determine gender.
The “chapters” of our genetic information, found within each chromosome, are the genes. Like chromosomes, we have two copies of every gene. Out of the thousands of genes we have, there are a handful of genes that have been associated with Usher syndrome. We all have these “Usher syndrome genes” but individuals with Usher syndrome have changes in one of these genes, almost like a spelling error or paragraph missing, which doesn’t allow that gene to give the instruction to the body in the way that it should. Usher syndrome is a recessive condition, meaning that BOTH copies of a gene associated with Usher syndrome need to be impacted for an individual to have Usher syndrome. Carriers, meaning those who have one working copy of an Usher gene and one non-working copy, do not have features of Usher syndrome, because the working copy almost acts like a back-up instruction book, covering for the one that is not working. Approximately 1 in 70 individuals in the population are carriers for Usher syndrome and when two carriers for the same genetic type of Usher syndrome have children, they have a 25% (or 1 in 4) chance of having a child with Usher syndrome.
Now that we have just reviewed the genetics behind Usher syndrome, what more can a genetic counselor add to your care?
Pin-pointing the genetic cause: Finding out the exact genetic cause of Usher syndrome in you and/or your family is not going to change the overarching diagnosis of Usher syndrome. However, this information can be used to determine the genetic subtype of Usher syndrome. Why is this important? First, there are several genes associated with Usher syndrome and while they have a lot of overlap they all act slightly differently. At the cell level, things are happening differently in that instruction book depending on the genetics, but on the surface, these small cellular/genetic changes may have the same big picture effect. Many clinical trials or research studies target things at the smaller cellular level to a particular genetic subtype; therefore, genetic classification is often necessary to enroll in clinical trials or research studies. In addition, defining the genetic subtype might be able to provide information about additional features or progression. Second, knowing the genetics makes it easier to test family members. The particular genetic changes can be tracked through the family much more easily once we know what we are looking for. Finally, and most importantly, you are unique! Providing the most context and information from your genetics means your healthcare team can tailor their care just to you. This is what “personalized medicine” is all about. Finding the genetic cause of Usher syndrome is the first step. It may only seem like small changes now, but this is the future direction of medicine.
Family History: Gathering a family history can feel like a lot of personal questions dragged out over at least three generations. I assure you, a genetic counselor’s family tree documentation, called a pedigree, can hold a lot more information than it may appear. A pedigree holds information about Usher syndrome in the family and can help identify other family members who should be offered genetic testing. I often get the question, “We are done having kids, so why does this testing matter?” The answer is that our genetic information is shared back through many generations and impacts not just you, but your children, siblings, sibling's children, cousins, aunts, uncles, and so on. This might be information they are interested in having and by recording those family members, a plan can be made as to how to spread the appropriate information through the family tree. Beyond the direct context of Usher syndrome, it’s pretty nifty to have your family tree recorded and integrated into your medical history. A genetic counselor may uncover clues to things in the family which may warrant additional follow up and were not recognized until organized into a structured tree. Gathering a family history can be helpful to your health beyond Usher syndrome, now and in the future.
Things Change: What we know now is different than what we knew last year, and this will be different than what we know next year, and so on. That is the nature of genetics. Creating a relationship with a genetic counselor can ensure that new information from the field is brought directly to you and integrated into your care.
Resources and Support: Genetic counselors are trained to be able to identify and locate resources for you. If you are reading this blog, you have already found the Usher Syndrome Coalition, but what about trying to find a specialist close to a family member in Kalamazoo, or trying to figure out how to tell your second cousin you only see once every third Leap Year about genetic testing? Figuring out how genetic testing is ordered and how to navigate insurance coverage are equally important questions. Genetic counselors can help with all of this and more! Support can span the present and the future, too. Many of you reading this may be parents of young children with Usher syndrome- how might your children react and feel through various stages of their development about Usher syndrome? How can you prepare for stages and conversations you foresee in your family? Genetic counselors can provide support and tools to help prepare you for these things throughout you and/or your child’s lifetime. We can identify needs, facilitate additional referrals, and connect with social workers or counselors if more support is needed. We know that every family and person has different needs, and our goal is to work with you to provide the resources individualized to you. And lastly, it’s sometimes just nice to talk things out. We are here for you!
If I still haven’t convinced you that genetic counseling is right for you, that’s ok too. A central tenet of genetic counseling is the empowerment of patients to make informed decisions through education. Consider this my brief attempt at education. I am hopeful, however, that you are interested in learning more about genetic counseling or meeting with a genetic counselor to learn about how genetics impacts you and your family.
Here are a few ways to get started: First, for those attending the family conference this July, there will be genetic counseling session available on Saturday, July 12th. More information can be found here: Usher Syndrome Family Conference. Second, both the National Society of Genetic Counselors (NSGC) and the American Board of Genetic Counselors (ABGC) have “Find a Counselor” tools listed online (NSGC Find a Genetic Counselor and ABGC Find a Genetic Counselor). If you live outside of the US, I encourage you to ask local hospitals if they have genetic counselors or reach out to counselors by email who may be able to point you in the right direction.
It’s cheesy, but it’s true - We are here for you. Don’t be shy. How can we help you?
Katherine Lafferty is a certified and licensed genetic counselor in Massachusetts. She is currently a genetic counselor at the Laboratory for Molecular Medicine at Partners HealthCare Personalized Medicine in Cambridge, MA where she and her colleagues work at the forefront of clinical genetic testing in the areas of hearing loss and Usher syndrome. Katherine also provides genetic counseling to patients and families in the Department of Otolaryngology at Boston Children’s Hospital. In addition, she acts as Laboratory Curriculum Advisor, lecturer, and student supervisor for the Genetic Counseling Program at Boston University School of Medicine. Katherine can be reached at KLAFFERTY@partners.org.