Narrator: This is Science Today. Mitochondria are the power plants of cells - helping control body temperature and the synthesis of ATP, a chemical form of energy. Researchers at the University of California, Irvine have discovered that key mutations in the mitochondrial DNA of migrating early humans helped them adapt to colder climates and may even play a role today in why certain people are prone to certain diseases. Study co-leader Douglas Wallace, explains mitochondria are the major source of oxygen radicals in the body.
Wallace: If your mitochondria are burning very hot and fast, then all of the calories are going to be making heat but if they're burning sluggishly, more of the calorie energy will go up in smoke and you'll get more oxygen radicals.
Narrator: Oxygen radicals kill off cells and lead to several age-related diseases.
Wallace: So what has been found is that the people with the mitochondrial DNA lineages that have the tendency to make more heat, they are protected against Alzheimer's and Parkinson's disease.
For Science Today, I'm Larissa Branin.