What is mitochondrial DNA and why would it play an important role in aging?
Not all of our DNA is found in our nucleus. Some is actually found in small organelles within cells called mitochondria. Scientists think these mitochondria have their own pool of DNA because they were once small free-living creatures. Sometime in our distant past, our ancestors absorbed them and now mitochondria make our energy. It turns out that mitochondrial DNA (mtDNA) gets mutations much faster than the DNA in the nucleus. One reason for this is thought to be the presence of ROS or reactive oxygen species (also known as free radical) in the mitochondria. When mitochondria make energy for us, they create ROS that can damage nearby mtDNA. In fact, this might be the reason why eating less leads to longer lives in animalsless food, fewer ROS. The idea is that as mtDNA becomes more and more damaged, the mitochondria cannot produce energy as well and become dysfunctional. This could lead to aging and ultimately, death. Is there any way to test this idea directly? The most direct way to
