In 2018, people started using the blockchain to battle deepfakes, track sushi-grade tuna from Fiji to Brooklyn, and even cast a (symbolic) vote. It was only a matter of time before someone figured out how to put all 6 billion bits of your genetic source code on the blockchain too. Starting this week, a startup called Nebula Genomics is doing just that, offering whole-genome sequencing for free, as a way to stock up for its real ploy: a blockchain-based genetic marketplace.