Scientists have identified a gene essential to the ability to sense pain, a discovery which could be a potential target in the development of new pain relief medications.
The researchers also say there are people who have a mutant copy of the gene and are unable to feel pain from birth.
These people can’t distinguish between unpleasant heat or cold but their other senses, including touch, remain intact.
The study, of people with the rare condition Congenital insensitivity to pain (CIP), is published in the journal Nature Genetics.
The target of new research, to help develop treatments for chronic pain, will be the protein produced by the pain gene.