Scientists cite mutation as cause of inherited pain disorder

Scientists have made a new discovery that could pave way for a new treatment for a rare inherited pain disorder and could lead to a better understanding of chronic pain in humans.

The scientists have identified a mutation that enhances the function of a specific ion channel and causes a rare inherited pain disorder called familial episodic pain syndrome (FEPS). Ion channels are proteins that span the cell membrane and govern the movement of ions into or out of the cell. Ion channel function is critical for many different cell functions, and disruptions in specific channels have been linked with migraine, epilepsy, and multiple pathological pain disorders.

"Transient receptor potential (TRP) channels are ion channels that have been implicated in all aspects of sensation. However, despite mouse studies suggesting that a number of TRPs play an important role in pain pathways, no human heritable disorders of pain sensation have as yet been linked to mutations in TRP channels," explains study author, Dr. John N. Wood from the Wolfson Institute for Biomedical Research at University College London.

The mutation is caused in the gene TRPA1.

"It was already established that TRPA1 is expressed in pain receptors in rodents and humans and that it plays an important role in response to environmental irritants in mouse models," says Dr. Ruiz-Linares.

"We discovered a gain-of-function mutation associated with FEPS that could give rise to stereotyped episodes of severe pain affecting principally the upper body."

"Our findings provide the first evidence that variation in the TRPA1 gene can alter pain perception in humans," concludes Dr Wood.

"It will be of great interest to establish whether TRPA1 channel variants or misregulation contributes to the risk and severity of chronic pain in other patient populations."

The research is published by Cell Press in the June 10 issue of the journal Neuron.