Researchers have found a way to improve the accuracy of a genome editing technique based on the CRISPR-Cas9 system. They developed enzymes that can precisely target DNA with a lower risk of introducing unwanted mutations. These enzymes could be a step forward towards making base editing more feasible in treating genetic diseases. Base editing is a technique used to convert one DNA letter into another (unlike conventional CRISPR-Cas9, which relies on cutting DNA). The advantage of base editing is that it offers a greater degree of control, but it can also introduce random changes to the genome. The newly developed enzymes are less likely to determine such changes, making it safer for researchers to develop genome editing therapies. The new technique still needs further improvements to avoid, for example, the risk of unwanted DNA edits that could cause harm.