Family that doesn’t feel pain holds key to better pain relief

Due to the failure to experience pain as a result of accidents, the family often have fractures that go undetected and this leads to inflammation in their bones.

Scientists are studying a family in the UK, whose members are insensitive to pain, in the hope of discovering a gene mutation in their DNA that might help in the development of therapy for chronic pain.

Researchers believe the condition could be a result of some nerves not reacting or functioning properly.

The Marsili Syndrome is named after the family, whose members are hyposensitive, or less than normally sensitive to extreme heat, capsaicin in chilli peppers and have experienced pain-free burns and bone fractures, with the sensation of pain being fleetingly momentary.

Fifty-two-year-old Letizia Marsili, her mother, two sons and niece are affected by the syndrome named after their family.

Due to the failure to experience pain as a result of accidents, the family often have fractures that go undetected and this leads to inflammation in their bones, as well as burns and injuries that go undetected, so much so that Ludovico Marsili, 24, continues playing football long after suffering a fracture without notice. X-rays showed he had previously undetected micro-fractures on both ankles.

GENE MUTATION

Initial analysis by researchers showed that the Marsili family have normal nerves, but they don’t function as they should. After mapping out the protein-coding genes in each family member’s genome, researchers found a mutation in the ZFHX2 gene.

Two subsequent studies conducted in test mice bred without this gene found that their pain thresholds had significantly been altered. When scientists bred a new line of mice with the relevant mutation, they found the mice to be notably insensitive to high temperatures.

The researchers are now exploring how the mutation affects pain sensitivity and to see if there are other genes involved.

This may lead to advances in pain relief through gene therapy especially for people with chronic pain conditions such as arthritis and back pain.

“We’re working to gain a better understanding of exactly why they don’t feel much pain, to see if that could help us find new pain relief treatments,” said lead author Dr James Cox, from University College London. The findings were published in the journal Brain.