A young Pakistani street performer and members of three related families have enabled scientists to make a genetic breakthrough that could lead to more effective painkillers.
During his short life, the unnamed boy never felt pain. He was a local celebrity in northern Pakistan, where he astonished crowds by plunging knives through his arms and walking on burning coals. He died on his 14th birthday after jumping from a roof.
By studying his case and members of families in the same clan, researchers have discovered that they all had a rare inherited genetic mutation that stopped them feeling pain.
"All six affected individuals had never felt any pain, at any time, in any part of their body," said Dr. Geoffrey Woods, of the University of Cambridge Institute for Medical Research in England.
The mutation that Woods and colleagues in Britain and Pakistan have discovered is on a gene called SCN9A. It stops the functioning of a sodium channel, which produces nerve impulses that convey pain signals to the brain.
Drugs that block the function of the channel "have the potential to produce new and potentially safer analgesia," said Woods, who reported the discovery in the journal Nature.