Kevin Davies’s Editing Humanity takes you on a dizzying tour of CRISPR, from its discovery and naming by little-known Spanish microbiologist Francisco Mojica 25 years ago to the births of Lulu and Nana, the world’s first genetically edited humans. It took 13 years for the Human Genome Project to sequence the 3 billion bases in the human genome for the first time. Using a technique called micropore sequencing, you can now have yours done in less than 24 hours.Along the ride, you learn first about how CRISPR (clustered regularly interspersed short palindromic repeats) and its associated enzyme Cas-9 can be used to insert, modify, or delete DNA sequences in almost any organism. Although the system is an antiviral memory-enhanced immune system in bacteria, it can be used in almost any organism, since we all share the same basic DNA systems.The best-known researchers in this field include Nobel laureates Jennifer Doudna and Emmanuelle Charpentier, and George Church and Feng Zhang of the Broad Institute of MIT and Harvard, who currently hold the patents for most applications of the technique. A PhD in molecular genetics, Davies clearly explains the workings of the CRISPR-Cas9 system, using several colored diagrams, as well as the ongoing legal battles that will determine who will ultimately control the multibillion-dollar rights to a prokaryotic immune system.And the ride also goes worldwide. Davies brings you into interviews he does in Boston, Banff, Oslo, Singapore, Alicante, Vilnius, and Toronto, among many more. There are several reasons why I liked this book more than the four others I’ve read about CRISPR in the past two years. He explains the science without talking down to the reader. Yet he also explains the people. While in Toronto covering the Gairdner Awards (the “Nobel Prize” of Canada), Doudna and Charpentier share the award with a certain American epidemiologist named Anthony Fauci.Although most researchers (and legally some countries, including the USA) in this rapidly changing field maintain a moratorium on editing the human germ line, Chinese researcher He Jiankui, educated at Rice and Harvard, was the first to breach this barrier in 2018 with CRISPRd twin girls. He modified the CCR5 co-receptor for HIV, with the goal of making them immune to AIDS. Whether it really worked and whether there were additional off-site edits is still unknown. The uproar in the scientific world embarrassed the Chinese government, and Jiankui is currently in what amounts to house arrest, even though it is widely believed that the government knew exactly what was going on, turning a mostly blind eye. Many also believe that the Chinese will not allow such a gifted man to stay on the shelf for long, and in exchange for not naming officials in China who were complicit, Jiankui will be rehabilitated in the next few years.In the last few chapters, we learn about additional techniques, possibly more precise than the find-and-replace-all CRISPR, such as TALENs, ZFN, and single base editing. As microbiologist Fyodor Urnov wrote, “We live in an age where there is such a thing as Microsoft Word for human DNA. The cat is out of the bag, the genie is out of the bottle.