A 22-year study of abnormally short individuals suggests that growth-stunting mutations also may stunt two of humanity's worst diseases. Published in Science Translational Medicine, the study raises the prospect of achieving similar protection in full-grown adults by other means, such as pharmaceuticals or controlled diets.
The international study team, led by cell biologist Valter Longo of the University of Southern California and Ecuadorian endocrinologist Jaime Guevara-Aguirre, followed a remote community on the slopes of the Andes mountains. The community includes many members with Laron syndrome, a deficiency in a gene that prevents the body from using growth hormone. The study team followed about 100 such individuals and 1,600 relatives of normal stature.
Over 22 years, the team documented no cases of diabetes and one non-lethal case of cancer in Laron's subjects. Among relatives living in the same towns during the same time period, 5 percent were diagnosed with diabetes and 17 percent with cancer.
The Food and Drug Administration has already approved drugs that block growth hormone activity in humans. These are used to treat acromegaly, a condition related to gigantism.
Because studies have shown that growth hormone deficiency protects mouse and human cells against some chemical damage, Longo said his team would initially seek approval for a clinical trial to test such drugs for the protection of patients undergoing chemotherapy.
Growth hormone-blocking drugs such as pegvisomant appear to be well tolerated, Longo said. But even if chronic growth hormone blocking should come with a minor side effect, Longo predicted that societies and governments would make the trade in exchange for less chronic disease.
He called it the "square survival curve," where most of one's life is lived without major illness.
"It's the dream of every administration, anywhere in the world. You live a long healthy life, and then you drop dead," Longo said.