A scramble for a new generation of pain treatments began when scientists zeroed in on a gene called SCN9A, which makes a molecule present in nerves (called Nav1.7) that is a key player in transmitting pain to the brain.
Evidence for the gene’s central role came from people with strange inherited syndromes. Some mutations in the gene cause people to feel more pain. The Pakistani boy, meanwhile, was a member of a family with a mutation that disabled SCN9A entirely.
There are some downsides to fooling with pain. People with the no-pain DNA mutation have a limited sense of smell, and without pain, they don’t know when they are injured. A number of members of the Pakistani family were limping from broken limbs. Others had lost parts of their tongues—they’d bitten them off.
There are still plenty of unanswered questions about whether CRISPR will be a useful pain fix, including how long the effect will last and how it would affect preexisting pain, something the researchers didn’t look at. Gene therapy is also high-tech and very expensive—one recently approved treatment costs $2.1 million.
In addition to the no-pain mutation, there’s a genetic variant that could let an air traffic controller—or a soldier—get by on four or five hours of sleep per day. As gene-therapy techniques advance and become less expensive, it might be feasible to routinely enhance people with similar genetic changes.