It’s safe to say that when I stubbed my toe this morning, I wasn’t feeling particularly grateful for the throbbing pain. Researchers say our ability to feel pain is nonetheless important, as it warns us to dangers in the environment and stops us from seriously hurting ourselves. Those who are unable to feel pain end up with a mounting number of self-injuries and a shorter lifespan. By studying such individuals, researchers may have found the underlying gene necessary for making pain-sensing neurons. The study, published in the journal Nature Genetics, could lay the foundations for the development of new pain treatments for those who don’t feel any and for those who feel too much.
Congenital insensitivity to pain with anhidrosis (CIPA) is the rare condition where suffers are unable to feel pain. A life without pain, however, is filled with its own agonies, as The Guardian points out. The most famous example being 16-year-old Ashlyn Blocker, living in the United States, who has had a number of serious injuries over the years, including feeling no pain after putting her hand in boiling water, but seeing she had burnt her skin off.
"The ability to sense pain is essential to our self-preservation, yet we understand far more about excessive pain than we do about lack of pain perception," says co-author Professor Geoff Woods from the Cambridge Institute for Medical Research at the University of Cambridge. "Both are equally important to the development of new pain treatments—if we know the mechanisms that underlie pain sensation, we can then potentially control and reduce unnecessary pain."
Researchers genetically mapped 11 families across Europe and Asia, looking at 158 individuals affected by CIPA in order to search for the underlying genetic cause of the disease. The results showed that those who suffered from the disease had 10 different mutations within the gene called PRDM12. Those carrying two copies of the mutated gene developed the disease, but those with only one copy were unaffected. Researchers further explored the role of PRDM12 in making pain-sensing neurons in mice and frog embryos. They found that PRDM12 is vital for the development of pain-sensing neurons, and a mutated gene would result in a block in the development of these neurons and an insensitivity to pain.
"We are very hopeful that this new gene could be an excellent candidate for drug development, particularly given recent successes with drugs targeting chromatin regulators in human disease," says first author Dr. Ya-Chun Chen, from the University of Cambridge, in a statement. "This could potentially benefit those who are at danger from lack of pain perception and help in the development of new treatments for pain relief."