The link between genetics and mental illness continues to engage Abram Hostetter, a psychiatrist who is in his fourth decade of world-recognized research into why Old Order Amish are more susceptible to bipolar disorder than the general population.
Hostetter, an alumnus of two Mennonite colleges, is part of a University of Miami team that has been researching mental illness among generations of Amish families in Lancaster County since 1976.
He and project leader Janice Egeland, professor of psychiatry, behavioral sciences, epidemiology and public health at the University of Miami, worked for years together out of an office in Hershey, Pa. They assembled a team of about a dozen others to assist them.
鈥淭he Old Order Amish of Lancaster County have a lower incidence of mental illness than the general population, but a much higher incidence of bipolar disorder, 鈥� said Hostetter.
Bipolar disorder, also called manic depression, often leads to suicide. 鈥淚t鈥檚 in the blood,鈥� said an Amish grandmother鈥攐r siss im blut, in Pennsylvania German鈥攚hen Egeland began her research.
Bipolar disorder is characterized by episodes of mania or depression that typically recur and often become more frequent and severe during a lifetime. It鈥檚 estimated that about 1 percent of the U.S. population has a major mood disorder.
Over the years, scientists discovered an association between mood disorders and two known genetic markers. In other words, people suffering from bipolar disorder have inherited it from their parents.
Hostetter and Egeland found that Old Order Amish families are ideal subjects for genetic studies for a number of reasons:
- They descend from a limited number of pioneer couples who came to America in the 18th century.
- There is little marriage to outsiders or other forms of in-migration, causing the Old Order Amish of Lancaster to form a closed gene pool
- They have large families and keep extensive genealogical records.
- They prohibit the use and abuse of alcohol and drugs, which often mask the symptoms of bipolar disorder.
鈥淲e have a total pedigree of the Old Order Amish community in a computer from the original 32 adults who came in the 1760s until in the 1970s,鈥� said Hostetter, 鈥渟o we can determine what percentage of genetic endowment any two people share.鈥�
The research team focuses on the original 鈥減edigrees,鈥� or cohort. About 65 percent of the families are named Stoltzfus. Other names are King, Zook, Lapp, Beiler, Petersheim, Blank, Fisher, Miller, Glick, Esch and Smoker.
Hostetter grew up in Lancaster County in a Mennonite family and knew some Amish families with bipolar disorder. His grandfather, who was longtime moderator of , often consulted with Amish ministers. Hostetter鈥檚 father was a farmer and tobacco broker and also had much interaction with the Amish.
鈥淢y best friend, an Amish boy, in elementary school had bipolar disorder, as did his mother and grandmother,鈥� said Hostetter. 鈥淗e committed suicide at age 18 and his sister committed suicide in the 1990s.鈥�
Hostetter was a at 草莓社区 for two years in the late 1940s. He earned his bachelor鈥檚 degree from Goshen College in 1953. He graduated from Jefferson Medical College in Philadelphia and trained in psychiatry at Norristown State Hospital.
He joined a private practice in his home area and later formed a group practice in Hershey, where he met Egeland, who was on the faculty of . 鈥淲e first spoke about using the Amish population in Lancaster County to solve the medical puzzle about inheritance of bipolar disorder in 1970,鈥� he said.
Egeland and Hostetter both joined the faculty of the University of Miami but worked out of what they called 鈥淯niversity of Miami, North Office鈥� in Hershey.
Nine years ago Hostetter retired from his psychiatry practice at age 74 and moved with his wife to Charlottesville, Va. He returns to Pennsylvania about five times a year, though, to pursue his research. In December 2012 he joined Egeland there.
鈥淲e worked on 鈥榗oding鈥� cases to detect particular characteristics of each of their manifestations of illness,鈥� he said. 鈥淲e have very detailed medical histories and DNA samples on over 100 bipolar patients.鈥�
鈥淎t this point,鈥� Hostetter continued, 鈥渨e are on the verge of whole genome sequencing for 80 subjects, still attempting to locate all the specific genes involved.鈥�
Hostetter noted that bipolar disorder is treatable and that persons with the illness can lead normal lives. 鈥淗owever, untreated or inadequately treated, there is still a 15 percent suicide rate, to say nothing of the suffering and turmoil these people have and put their families through,鈥� he said.