By Julie Cunningham
The discovery of a human gene linked to hereditary obesity may allow scientists to develop a cure for the disease, and has once again revealed the significant association between obesity and type 2 diabetes.
Scientists at Myriad Genetics in Salt Lake City teamed up with the University of Utah for the Human Obesity 1 gene project. The discovery of the obesity gene, HOB1, was announced earlier last week.
“Obesity is an area of great medical importance, and there aren”t any really effective medications currently on the market,” said Bill Hockett, vice president of corporate communications for Myriad Genetics. “There are a couple of things that help with dieting, but they are not the same as a drug that could really make a huge difference in people”s lives like one based on this HOB1 gene.”
This discovery is the first to demonstrate the significance of gene heredity in human obesity, Hockett said. Obesity genes discovered in the past only proved to be important in mice, rats or other animal model.
Hereditary obesity is a metabolic defect, and people with this disease will gain weight even though they consume a normal amount of calories, Hockett said. The calories are stored as fat rather than used for energy, which leads to the weight gain.
Scientists are using HOB1 to develop two new products that may help with hereditary obesity, Hockett said. One product is a diagnostic test that would make it possible to determine if a person has a mutation of the HOB1 gene that is causing their obesity.
The second is the development of a drug that would block the protein produced by the HOB1 gene that is causing the weight gain, Hockett said. Once this protein is blocked, a person could start metabolizing food normally and be able to lose weight.
The discovery of HOB1 also has established more scientific evidence of the link between obesity and type 2 diabetes.
“Once we found this gene, we looked in our disease network for diabetes, where we have mapped out the protein interactions that cause diabetes, and there was HOB1 right smack in the middle of the diabetes network,” Hockett said.
“This gene may help to explain on a molecular basis what everybody has been seeing out there in the clinics. Obesity is a very strong risk factor for type 2 diabetes,” he said.
Type 2 diabetes causes a person to be resistant to the insulin his orher body produces. Insulin is necessary for the body to metabolize sugar, starches and other food into the energy that cells in the body use, according to the American Diabetes Association Web site.
“How obesity causes type 2 diabetes is not known, but the association between the two is very obvious,” said Dr. Joseph Miner, Utah County Health Department executive director. “The more obese you are, the more resistant your cells are to responding to the insulin, therefore causing you to have high blood sugars.”
Unlike type 1 diabetes, many sufferers of type 2 who are diagnosed with diabetes because of their weight, Miner said.
“There are many good examples of how weight loss definitely helps improve management of type 2 diabetes,” Miner said. “They very likely won”t need any insulin and can be managed with oral medications and pills. Sometimes they don”t even need that.”
The newly discovered HOB1 gene may reduce the incidence of other diseases that have been linked to obesity, such as heart disease, stroke, hypertension, and some types of cancer, by reducing the incidence of obesity, Hockett said.
“The primary goal is to help individuals who are severely obese get back to a normal weight and reduce the likelihood of other diseases in the future,” he said.