Pain is useful: It tells us when our bones are broken, when we’re in water that’s going to scald us and when we’re otherwise harming our bodies.
Then we can change course, end the pain and stay out of harm’s way. That’s the hope, at least.
But for one Italian family, pain as the average human experiences it is utterly foreign. And a new study of the family, published this week in Brain, a neurology journal, pinpointed exactly why some members of the Italian clan are pain-free.
As the researchers would put it, the family has “a reduced capacity to detect tissue-damage causing stimuli.” The family is otherwise normal, researchers said, but six members across three generations don’t experience pain — whether that be the hottest heat, the coldest cold or even a broken bone.
“Sometimes they feel pain in the initial break but it goes away very quickly,” Dr. James Cox, the lead author of the University College London research, told the New Scientist. “For example, Letizia broke her shoulder while skiing, but then kept skiing for the rest of the day and drove home. She didn’t get it checked out until the next day.”
The phenomenon is called the Marsili syndrome, named after the Italian family researchers studied.
Understanding the genetic quirk that gives the Italian family pain-free lives is a breakthrough that could, down the road, lead to new and improved therapies to manage chronic pain, Cox said in a statement.
University College London researchers estimated that one in 10 people suffer from “moderately to severely disabling chronic pain” — the kind of pain that stops being useful and starts being debilitating. That makes it particularly attractive to seek novel treatments for pain beyond common painkillers.
To complete their research, the researchers mapped the protein-coding genes in each family member’s genome, based on DNA taken from blood samples of each.
Then researchers were able to zero in on “a novel point mutation” in the ZFHX2 gene as the cause of the syndrome, they said. And when researchers replicated that mutation in mice, they found the rodents also became markedly less sensitive to temperature.
Now that scientists have pinned down the mutation, researchers are looking to figure out precisely how it operates.
“With more research to understand exactly how the mutation impacts pain sensitivity, and to see what other genes might be involved, we could identify novel targets for drug development,” co-author Professor Anna Maria Aloisi of University of Siena said. Aloisi was part of the team that discovered Marsili syndrome.
Plenty could benefit if those new drugs or therapies came to fruition.
There are “millions of people worldwide who experience chronic pain and don’t get relief from existing drugs,” according to another study author, Dr. Abdella Habib of the Qatar University College of Medicine.
The pain-free Italian family is made up of a 78-year-old matriarch, her two daughters, who are 52 and 50, and their three children — two boys, 24 and 21, and a girl, 16.
Someday it might be possible to reverse the family’s pain-free condition, study author Cox told the New Scientist.
But the family isn’t interested: “I asked them if they would like to normally sense pain and they said no,” Cox told the website.