Adenine base editor excels at fixing point mutations

Abstract

Many diseases are caused by single-base mutations in genomic DNA. Scientists have long searched for methods to correct such mutations to treat these genetic diseases. Last year, David R. Liu of Harvard University and coworkers developed a technique called base editing that fixes some single-base mutations. It changes a cytosine-guanine (CG) base pair to a thymine-adenine (TA) pair at a targeted genome site (Nature 2016, DOI: 10.1038/nature17946 and C&EN, April 25, 2016, page 5). A missing feature was the ability to go in the opposite direction, AT to GC. Liu’s group has now developed adenine base editing, which does that (Nature 2017, DOI: 10.1038/nature24644). Base editing uses a component of the popular genome-editing technique CRISPR, but it has some advantages over the standard CRISPR method. CRISPR is ideal for inserting and deleting DNA sequences at targeted locations. In contrast, base editing has the edge for single-base changes: It is more