Amish people living in a rural part of Indiana have a rare genetic mutation that protects them from Type 2 diabetes and appears to significantly extend their life spans, according to a new study.

The findings, published on Wednesday in the journal Science Advances, shed light on the processes underlying cellular aging and could lead to new therapies for chronic diseases, some experts say. The researchers are planning at least one follow-up trial that will recreate the effects of the mutation so they can study its impact on obese people with insulin resistance, a precursor to diabetes.

The mutation described in the new paper affects a mysterious protein called plasminogen activator inhibitor-1, or PAI-1, that is known primarily for its role in promoting blood clotting. The mutation was first identified in 1991 in a secluded Amish farming community in Berne, Ind. An estimated 5 percent of the community carries the mutation, which causes them to produce unusually low levels of PAI-1.

Scientists have long suspected that PAI-1 has other functions outside of clotting that relate to aging. Dr. Douglas Vaughan, a cardiologist at Northwestern medical school, noticed, for example, that mice that had been genetically engineered to produce high levels of the protein age fairly quickly, going bald and dying of heart attacks at young ages. People who have higher levels of the protein in their bloodstreams also tend to have higher rates of diabetes and other metabolic problems and to die earlier of cardiovascular disease.