A Chinese gene-editing experiment has lost touch with patients whose DNA has changed, alarming The Wall Street Journal reports . The gene-editing tool known as Crispr-Cas9 allows scientists to edit the DNA of patients in hopes of eliminating harmful mutations, such as those that cause cancer. However, Chinese scientists have reported leapfrogged in human beings in the last few years. Beijing has no federal body that oversees gene-editing trials, meaning standards vary across experiments. The approach has been troubling to doctors and scientists in the United States, who fear the science could be overshadowed by haphazard implementation. Last month, a Chinese scientist claimed he created the world's first gene-edited babies. Jennifer Doudna, a professor of chemistry and molecular & cell biology at the University of California Berkeley who is credited as a co-inventor of the Crispr technology, responded to the claim. The fidelity of the gene-editing process can not be evaluated, "Doudna cautioned.