BarbaraHudson writes Researchers figured out how to label and keep track of new pieces of DNA, and learned to follow the enzyme responsible for copying those pieces. Their research focused on enzymes called polymerases. These enzymes create small regions in DNA that act as scaffolds for the copied DNA. Scientists assumed that the body deletes the scaffolds containing errors, or mutations, and the standard computer models supported this theory. However, the actual research showed that about 1.5 percent of those erroneous scaffolds are left over, trapped within the DNA. After running models, scientists now believe they can track how DNA replicates and find the most likely areas where these scaffolds with errors turn up. The erroneous scaffolds usually appear close to genetic switches, those regions that turn on when genes activate. The mutations damage the switch, which results in genetic disease, as well as increasing the likelihood of cancer.