Pitt research team to help seek out anorexia nervosa gene
October 23, 2002
Anorexia nervosa has existed for hundreds of years, has the highest death rate of any… Anorexia nervosa has existed for hundreds of years, has the highest death rate of any psychiatric disorder, and psychiatrists have no known treatment for it.
However, a research team at Pitt, along with researchers across the United States and in Europe, is studying anorexia in a new way that may yield effective diagnostic techniques and treatment therapy.
A few weeks ago, Pitt embarked on a new five-year study to investigate whether there are genes that can influence a person’s risk for anorexia. The National Institute for Mental Health has granted $10 million to fund researchers working at 10 data collecting sites and one data analysis center at Pitt. Two weeks ago, the research teams met for a personnel-training session and to establish methods for collecting data.
The data collection and analysis sites, which are located nationwide as well as Toronto, Munich, Germany, and Pisa, Italy, are trying to find 400 families with two or more members that have anorexia nervosa. These family members will undergo both blood tests and psychiatric assessments in order to provide the genetic and behavioral data that will allow psychiatric and genetic research teams to start their search for a connection.
This new study will continue the work of previous studies of anorexia’s relationship to genetics that were funded by the Price Foundation, a private organization in Europe that supports eating disorder research.
The research teams will follow processes used in the Price Foundation studies and first focus on examining study participants for certain behavioral traits that may contribute to anorexia.
Walter Kaye, professor of psychiatry at the School of Medicine and a co-principal investigator in the study, said these could include obsessionality, anxiety and perfectionism. He said the researchers then try to draw connections between the influence of the participant’s environment and any behavior traits that might be hereditary. “Behavior is always some kind of interaction between nature and nurture,” Kaye said.
He said the “nature” part involves analyzing the genetic makeup of the family members, whether they are relatives or siblings, in search of genes that might be responsible for these behavior traits.
By comparing the DNA samples of relatives of siblings, the researchers look for changes in genes, or alleles, that a participant may inherit and render them susceptible to anorexia.
However, Kaye said, this process is difficult and time-consuming, for while a participant’s genome, or overall genetic makeup, may be composed of at least 30,000 to 40,000 genes, the research teams want to isolate only a few.
Bernie Devlin, associate professor of psychology at the School of Medicine and another co-principal investigator, described this process as moving from a map of the world to a map of a city.
He explained that by using short tandem repeat markers, of repeating patterns or amino acids in a person’s DNA, geneticists map out sections of the genome and find areas to focus on.
Using technology that maps the genome according to patterns in amino acids, researchers can check for related DNA patterns between two family members affected by anorexia.
If two of these STR markers are close together on a chromosome, this means the genes near these markers are probably inherited as a group. If two related participants have DNA patterns near their genetic markers that are too similar to occur by chance, these genes are probably linked together. These excessively similar parts of a genome may contain genes that can influence anorexia.
So far, the researchers, in their previous Price Foundation studies, have found three areas of the genome where the genes influencing anorexia might be located. “It’s going to take years to find the genes,” Kaye said. “It’s not a short term process.”
However, Kaye emphasized the importance of studying anorexia in this manner. “We don’t have a treatment for anorexia because we don’t really understand it,” he said.
In addition to the high death rate, he added that changes in health care have made it more difficult to keep anorexia patients in treatment long enough to gain weight.
“I think it’s very important for supporting this as a disease that needs treatment,” Kaye said.
He added that recent improvements in DNA sequencing technology have made examining genes easier. This allows researchers to check for a biological aspect to diseases, such as anorexia, that have previously been attributed to environmental or societal factors.
The research teams are still searching for families that would be willing to participate. Anyone who is willing to help out can contact researchers by calling (888) 895-3886 or visiting their Web site at www.angenetics.org.