Scientists have tracked down a genetic mutation that makes some members of an unusual Pakistani family fail to sense pain.
Although pain can be agonizing, it does serve a useful function—it teaches people and animals to avoid dangerous situations and forces them to attend to wounds. However, a handful of people have genetic conditions that prevent them from feeling pain. This rare lack of sensation is often detrimental; people with the condition can be unaware of having suffered significant injuries.
Several years ago, medical geneticist C. Geoffrey Woods of the University of Cambridge in England and his colleagues began working with children from a family in northern Pakistan in which several members can't sense pain. The team's first research subject, a 10-year-old boy, was well known in his community for street performances in which he placed knives through his arms and walked on hot coals. Despite tissue damage, he apparently felt no discomfort.