by Antoine Costa
Researchers have discovered a mutation that makes all members of an Italian family insensitive to pain.
It’s a double-edged blessing. Congenital insensitivity to pain is a rare syndrome, linked to genetic mutations that are beginning to be identified and understood. The Marsili family, recently honored by the British media, is affected. Thanks to her, researchers at University College London and the University of Siena have identified the gene behind their strange power.
As the BBC mentions , the mother, Letizia Marsili, does not feel the burns and can fracture a bone without even noticing it. She broke the scapula on the ski without being alarmed, only going to the emergency room the next morning, because she felt tingling in her fingers. And since the gene in question is dominant, five other members of this Italian family are suffering from congenital analgesia: his mother, his two sons, his sister and his niece.
Which is not easy. About her son Ludovico, 24 years old and amateur footballer, she tells. “He rarely stays on the ground, even after being broke. (…) But the radio showed that he had a large number of micro-fractures in both ankles. In fact, insensitivity to pain testifies to the importance of pain as a signal of self-preservation. When this signal is weak or non-existent, it is very easy to put yourself in danger simply by inadvertence.
Towards a treatment of chronic pain
But the misfortune of some (potential) happiness of others, the sequencing of the genome of the members of the family allowed to identify the gene in cause, ZFHX2. Researchers have shown in mice that he codes for a transcription factor involved in the functioning of pain receptors located in the spinal cord. In the Marsili family, a point mutation prevents the gene from expressing the crucial protein.
As a result, despite a normal nervous network, the pain signal does not lead to a subjective sensation. “In truth, we feel the pain, the perception of pain, but it only lasts a few seconds,” says Letizia Marsili in the columns of the BBC.
The identification of the causative gene could help treat chronic pain, a scourge that affects an average of one in ten people. “If we find a way to mimic Marsili syndrome by overexpressing the mutated transcription factor, we could end up with gene therapy,” concludes Dr. Abdella Habib of Qatar University, lead author of the study. .