Research Roundtable Meetings

IDEAS sponsors bi-annual research roundtable meetings in conjunction with our international family conferences. These meetings provide an opportunity for researchers to discuss their current research on chromosome 15q duplications, engage in conversation with the IDEAS board regarding future research priorities, and explore opportunities for future collaborations.

2007 Research Roundtable Meeting
This meeting will take place on Thursday, June 28, 2007 from 8 a.m. – 12 p.m. at the Seaport Hotel in Boston, MA. Researchers interested in attending this meeting should contact Nicole Cleary, IDEAS Executive Director at .

2005 Research Roundtable Explores Link Between Chromosome 15q Duplications and Seizures
On June 22, 2005 IDEAS convened its third research roundtable meeting. This meeting represented the first time parents and scientists came together to explore the link between chromosome 15q duplications and seizures.

Family Perspectives
Our meeting started with five parents sharing their children’s experience with seizures. The scientists in attendance heard about seizures that started in infancy, in childhood and in adolescence. Families described how children started with one seizure type and other seizure types emerged as the child aged. Some seizures were easily controlled with the first medication, other seizures were controlled for awhile and then became more complex, and a few families described seizures that have never been controlled with medication. It was helpful for everyone to begin this meeting with the realization that over half of all individuals with idic(15) will experience seizures, but seizures are not uniform in their onset, their presentation or in their response to treatment.

Brenda Finucane, MS, CGC and Dr. Carolyn Schanen, members of the IDEAS professional advisory board provided an overview of the current understanding of the relationship of chromosome 15q duplications to seizures, drawing from the IDEAS seizure survey and Carolyn’s NIH funded study on the Molecular Investigations of Duplications of Chromosome 15 in Autism.

The meeting then turned to an examination of the role of gamma amino butyric acid (GABA). GABA is a major inhibitory neurotransmitter in the brain. There are three GABA_A receptor subunit genes in the chromosome 15q11-13 region. It is hypothesized that the abnormalities in these GABA_A receptor genes may play a significant role in the seizures experienced by people with chromosome 15q duplications.

Dr. Martin J. Gallagher from Vanderbilt University Medical Center in Nashville, Tennessee provided a very technical presentation regarding the many consequences of abnormal GABA_A receptor expression. He showed that even minor changes in the receptor structures can lead to human epilepsy syndromes. The methods that he uses to analyze the function of GABA_A receptors in the lab could be applicable to characterizing the effects of the extra copies of the GABA_A receptor genes in individuals with chromosome 15q duplications in isolated cells.

Dr. Diane Chugani from Wayne State University in Detroit Michigan provided information about her current study to measure brain GABA_A receptor binding in children with chromosome 15q11-13 mutations through the use of positron emission tomography (PET). Understanding of GABA_A receptor binding abnormalities in subjects with chromosome 15q11-13 duplications may lead to clues regarding the diverse presentation of seizures among individuals with this syndrome as well as to the autism and cognitive disabilities in these children. IDEAS will be collaborating with this study.

Dr. Art Beaudet from Baylor College of Medicine in Houston, Texas spoke about the role of the Prader-Willi/Angelman region in determining the clinical features in individuals with duplications of chromosome 15q. Dr. Beaudet’s research on genetic imprinting explores parent-specific gene activation (ie. genes coming from the maternal vs. paternal chromosomes). He suggested there is a fair amount of overlap in the phenotypes of individuals with Angelman syndrome and idic(15). Angelman syndrome is caused by an interstitial deletion/mutation in the maternal copy of chromosome 15q11 – 13 and the effects of idic(15) are more severe when caused by a maternal duplication of chromosome 15q11-13.

Dr. Timothy DeLorey at the Molecular Research Institute, in Mountain View, California provided the day’s final presentation. Dr. DeLorey has been involved in research with mouse models of Angelman syndrome. He provided information about the connection between chromosome 15 abnormalities, seizures and one of the GABA_A receptor subunits. He noted that some of the issues he has heard parents of Angelman patients discuss in regards to difficulty with seizure treatment he also heard from several parents of children with idic(15) at the roundtable.  He speculated that the similarities in epilepsy treatment difficulties in both Angelman and idic(15) syndromes could have the same root cause, but more research is necessary to investigate this possibility.

In terms of future research priorities, roundtable participants agreed that Dr. Chugani’s study provides a critical opportunity to learn more about what is happening with respect to how GABA_A receptors are functioning in the brains of individuals with chromosome 15q duplications. This will strongly impact the direction of future research in regards to both the seizures and other symptoms caused by chromosome 15q duplication syndrome. IDEAS will continue working toward the day when the relationship between chromosome 15q duplications and seizures is well characterized, and discussion of targeted and effective treatment options becomes a reality.