The mutation affected a gene called SCN11A, which makes a protein that controls how much sodium goes in and out of cells in the human body. That's a small job, but an important one. Nerves have many of these sodium channels, and they use their interior sodium concentrations to decide whether to send a signal—to pass on a message of pain, for example, or to call up a memory. The particular type of sodium channel that was mutated in Index Subject 1 is abundant in nociceptors, the types of nerves that sense pain. Sounds pretty relevant, right?