Scientists have a fever for genome tinkering, and the latest thing shooting up temperatures is CRISPR. The number of publications referring to CRISPR/Cas technology has mushroomed since its first use as a genome-editing tool in 2012. In a testament to the method’s popularity, a recent guest lecture at Vanderbilt University by CRISPR pioneer and 2015 Breakthrough Prize winner Jennifer Doudna packed a 300-person classroom and a 160-person overflow room—which then itself overflowed, recalls attendee Douglas Mortlock, a research assistant professor at Vanderbilt whoblogs about advances in CRISPR technology.