Stem cell research: UConn professor tracks cause of rare, genetic eating disorder

Like a code breaker, researcher Stormy Chamberlain is trying to find identification marks and figure out which is the “on” switch in a set of genes.

If she can solve the puzzle, she hopes to correct a rare, genetic disease that causes a person to have an insatiable appetite, often leading to obesity. Her work could not only lead to treatment of Prader-Willi Syndrome, but could shed light on what drives us to eat.

Dr. Stormy Chamberlain

Chamberlain, an assistant professor of genetics and developmental biology at the UConn Health Center in Farmington, is investigating the markers on the chromosomes to try to find those that turn on and off the genes.

In Prader-Willi, these genes are floating around in these patients, but they are not turned on as in the rest of the population. Instead, they are “silenced.” The goal is to eventually find medication that can be used to turn the genes on and repair the disorder.

Chamberlain, 36, is one of 18 researchers who won a portion of $9.8 million in stem cell grants in the latest round of state funding announced last week.

The state has committed to hand out $100 million in stem cell research grants over 10 years, and it has so far distributed $70 million. The money comes from the state’s tobacco lawsuit settlement.

Prader-Willi Syndrome affects one in 15,000 live births. In addition to causing a person to have an insatiable appetite, leading to overeating and obesity, symptoms include poor muscle tone, short stature, behavioral problems and sometimes autism-like symptoms. Babies with the disease have such poor muscle tone they are often referred to as “floppy” babies, Chamberlain said.

Physicians often treat the disease with growth hormones, which helps somewhat with the stature issue and overeating, and attention to diet, she said.

The disorder is caused when some genes are missing from the set of chromosomes the patient inherited from the father. A related disease, called Angelman Syndrome, is caused when these genes from the same region are missing from the set of chromosomes inherited from the mother. Surprisingly, symptoms for Angelman are very different from those in Prader-Willi. Angelman’s is characterized by severe developmental disability, speech difficulties, seizures, a happy demeanor and, often, hand-flapping movements.

In Prader-Willi Syndrome, the genes are silenced before the egg and sperm come together. It is possible that treatment could eventually take place in the womb or after babies are born, she said.

Chamberlain doesn’t know if her research will eventually lead to a cure, but she is hoping it can at least help ameliorate some of the problems.

Dr. Sally Rosengren, a physician at Connecticut Children’s Medical Center and the UConn Health Center, treats Prader-Willi patients. She estimates that 50 to 100 patients in Connecticut have the disease in Connecticut and said Chamberlain’s research could have a big impact on these patients and their families.

“It’s very hard on the families. It would be wonderful if there was a cure, rather than a treatment like a growth hormone,” she said.

Rosengren said research into turning on and off genes could someday help with other disorders, such as Angelman’s Syndrome and Beckwith-Wiedemann Syndrome, where the gene imprinting has been thrown off. Beckwith-Wiedemann Syndrome is a growth disorder that causes a large body size, large organs, abdominal wall defects, ear abnormalities and an increased risk of childhood cancer.

Chamberlain said she does not think her research can cure general obesity, but she said it could shed light on the issue.

“Everything we learn about Prader-Willi helps us learn what drives us to eat,” she said.

Chamberlain came to UConn Health Center about five years ago and is also a member of the UConn Stem Cell Institute. She grew up in Wyoming and said there is no special story or meaning behind her first name, Stormy, other than the fact that her parents, who are cattle ranchers, liked the name.

Chamberlain, who now lives in Oxford, first became interested in the field as an undergraduate at Princeton University, where she learned about genomic imprinting — tracking how some genes are expressed only from their mother’s or father’s copy of chromosomes.

She began doing graduate work on Prader-Willi at the University of Florida. Families who have children with this rare disorder sometimes feel overlooked, she said, particularly when they see how much attention is paid to other childhood diseases, such as cancer and diabetes.

“The thing that really cemented it for me was when I went to the Prader-Willi Syndrome Association meeting and met some of the families and the kids there. It put a human face to the science I was interested in already,” she said.

“Being able to put a human face on the disorders you work on makes you more passionate about what you do.”