Scientists are starting to crack the mystery behind one woman’s pain-free life. In new research, a team in the UK dove deep into the genetic make-up of Jo Cameron, a woman in Scotland with a rare mutation that leaves her practically incapable of experiencing physical and emotional pain. Among other things, the team found that her mutation seems to turn on and off a variety of other genes, including those linked to wound healing and mood.
Researchers at University College London detailed Cameron’s story in 2019, though they had first started studying her in 2013. At the age of 66, the woman had undergone hand surgery but remarkably needed no postoperative anesthesia afterward. A year earlier, she was diagnosed with severe joint degeneration in her hip but had none of the expected pain as a result. Throughout her life, she also reportedly felt little anxiety or fear and seemed to heal especially quickly from cuts and bruises.
When UCL researchers studied her extensively, they discovered two genetic mutations that appeared to explain her resilience, both connected to a pain-related enzyme known as fatty acid amide hydrolase, or FAAH. One was a deletion in a pseudogene (a region of DNA that resembles a gene but doesn’t code for a protein) that the team would go on to name FAAH-OUT; the other was in a gene nearby to the one that actually regulates FAAH.
Other studies have found that FAAH plays an important role in controlling our sensation of pain by breaking down a neurotransmitter that binds to our cannabinoid receptors. Studies of mice bred without the FAAH gene have shown that they experience less pain, for instance. But the woman’s unique condition—and the mutations that caused it—indicated that there are other ways that pain sensitivity can be influenced by our genetics.
Now, in a study published Tuesday in the journal Brain, the same UCL team is closer to understanding the underlying mechanisms behind the woman’s mutant powers.
The researchers used a variety of methods, including the gene editing technology CRISPR, to study the effects of the woman’s mutations on human biology. As expected, they found evidence that FAAH-OUT regulates the expression of FAAH itself. Her FAAH-OUT mutation seems to directly reduce levels of the enzyme, for instance. But they also found that the mutation appears to turn off and on hundreds of other genes. Some of these genes influence how fast we heal from wounds, while others affect our mood or levels of the body’s natural opioids. The findings also are the latest to show that so-called junk DNA has plenty of importance.
“The FAAH-OUT gene is just one small corner of a vast continent, which this study has begun to map. As well as the molecular basis for painlessness, these explorations have identified molecular pathways affecting wound healing and mood, all influenced by the FAAH-OUT mutation,” said senior study author and UCL researcher Andrei Okorokov in a statement from the university.
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Like any novel discovery, these findings will have to be validated by others. And even a pain-free life doesn’t come without struggles. People with these conditions have to be especially careful to avoid ignoring or missing serious injuries, for example. But the lessons learned from Cameron’s genetics could very well pay off in the future. Despite some early promise, pain treatments based on affecting FAAH directly haven’t panned out. But this research suggests that there are other avenues to try, and the UCL team is already planning to do so.
“As scientists it is our duty to explore and I think these findings will have important implications for areas of research such as wound healing, depression and more,” said Okorokov.