The mitochondria are rod-shaped organelles – the power generators (energy factories) of the cell. They convert oxygen and nutrients into adenosine triphosphate (ATP). ATP is the chemical energy "currency" of the cell that powers your cell's metabolic processes. An estimated 1 percent of all your DNA is found in these mitochondria. Unlike chromosomal DNA that is inherited from both parents, you get all your mitochondrial DNA from your mother. Mutations accumulate in mitochondrial DNA more quickly than in chromosomal DNA, so it's possible to trace your maternal ancestry way back beyond any relatives you may know by name—by tracking the inheritance of mutations in mitochondrial DNA. According to Dr. John Stamatoyannopoulos, for over 40 years the assumption has been that DNA changes affecting the genetic code solely impact how proteins are made—but this basic assumption about reading the human genome missed half of the picture. These new findings highlight that DNA is an incredibly powerful information storage device, which nature has fully exploited in unexpected ways.