Risk of Epilepsy in Families
Since we last spoke to you, we began a project in association with the Mayo Clinic in Minnesota. This project is a "population-based" study, meaning we have information about every person newly diagnosed with epilepsy who lived in the city of Rochester, Minnesota over a 60-year period (from 1935 to 1994). One of the main goals of the study is to obtain accurate information about the likelihood of developing epilepsy at particular ages, for close relatives (parents, siblings, or offspring) of people with epilepsy. We also hope to learn which clinical features of epilepsy indicate an increased genetic risk and to evaluate the accuracy of current diagnostic tools and criteria for the epilepsies.
Ethical Dimensions of Epilepsy Genetic Testing
In the past 30 years, genetic research on epilepsy has progressed rapidly, with more than 20 genes found so far that contribute to the development of various forms of epilepsy. Genetic tests are becoming available in the clinical setting and hold promise for confirming diagnoses and informing treatment. We know very little about how individuals and families feel about genetic testing and the impact that testing can have on an individual’s life. We are very interested in these issues and have begun to develop a line of research focused on genetic testing.
In 2009, Dr. Ottman chaired the Genetics Commission of the International League Against Epilepsy and published a report on the current state of genetic testing in the epilepsies. The report summarized current knowledge about epilepsy genetics and presented a framework to help physicians and researchers weigh the benefits and risks of genetic tests under different scenarios.
To explore this topic more thoroughly, we teamed up with a sociologist, Dr. Sara Shostak (now at Brandeis University), and began to look at genetic testing from the perspective of people with epilepsy and their family members. Through in-depth interviews with study participants, we found that people in families with epilepsy often form their understanding of how epilepsy is inherited based on the patterns of inheritance they observe in their own family. Participants in this study held a wide range of views about genetic testing and these views often differed depending on a person's stage of life (e.g., whether they were considering having children). Overall, participants said they may be interested in genetic testing but have some concerns. We hope to carry out another similar study soon to learn about the perspectives of even more people with epilepsy and their family members.
Epilepsy and Other Health Conditions
In 2008, Dr. Ottman worked with other epilepsy researchers across the country on a large-scale health survey. They surveyed 172,959 individuals to compare the rates of various health conditions in people who have epilepsy and people without epilepsy. They found that 2% of all respondents had ever had epilepsy or a seizure disorder. Compared with participants without epilepsy, those with epilepsy were more likely to report asthma, neuropsychiatric disorders such as anxiety, depression, or attention deficit hyperactivity disorder (ADHD), and pain disorders such as migraine headaches or chronic pain. These findings suggest that in order to create the best treatment plan for people with epilepsy, other health issues should be identified and considered. For example, if a patient has both epilepsy and migraine headaches, both problems could potentially be treated with a single drug that addressed both concerns.
For another ongoing study we are interviewing participants in families with epilepsy about their experiences with depression. This project is in collaboration with Dr. Gary Heiman in the Department of Genetics at Rutgers University. A number of studies have found that people with epilepsy are more likely to have depression than those without epilepsy, but the causes of this connection are not well understood. It is possible that depression is a side effect of epilepsy treatments, a consequence of irregular brain activity, a result of the psychological experience of having epilepsy, or some combination of all three.
We are so appreciative of everyone who donated blood samples to our study! Remarkable new advances have been made in laboratory techniques for analyzing the DNA. One of these new techniques, whole genome sequencing, enables us to read an individual’s entire genetic code and compare the codes across different individuals. Though sequencing analysis is still brand new and remains fairly expensive, it holds great promise as a tool for finding genes associated with heritable disorders. We received an economic stimulus grant to sequence some samples from our DNA library using this technology, and this project is currently underway.