No good parent wishes pain upon her child, but Verna Mahar wished it for two of her sons -- the eldest, Owen, most of all.
From the time he was a baby he was a roughhouser -- banging his head against walls and table corners without a whimper. When he was a toddler he'd bite his fingers to the bone unless she made him wear mittens indoors. His lips she could do nothing about: Owen chewed them happily until they bled.
"My husband and I didn't understand it. He didn't cry for nothing," Ms. Mahar said. "We couldn't understand why he wasn't feeling."
"Didn't it hurt?" she'd ask the growing boy. "No," Owen would say. "Well why not?" "I don't know, Ma."
Owen Mahar holds up a family photo of himself as a toddler. In the photo he is wearing mittens to protecting him from chewing his fingers. CIP children also chew on their own lips. Verna and Tom Mahar, of Bird Cove Newfoundland, have three children, and two of them have inherited two defective genes that cause the very rare condition called Congenital Indifference to Pain, or CIP. (Peter Power/The Globe and Mail)
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Not until Owen was 3 -- the year he broke a bone in his foot and kept right on walking -- did the family from Bird Cove, Nfld., receive an explanation. Doctors told them their son had a rare and storied disorder -- a genetic condition that prevents the ability to perceive pain. He is normal in every other way, able to distinguish hot from cold and pat from pinprick; only the sensation of pain does not register.
The Newfoundland family is one of only 15 worldwide known to be affected by congenital indifference to pain, or CIP. But the curse of their inheritance could become a blessing for the rest of the world.
Scientists have found the mutant gene behind the bizarre condition and believe that mimicking its effects could lead to a new age of painkillers.
An international research effort led by Vancouver biotech firm Xenon Pharmaceuticals Inc. has confirmed that a single mutant gene is responsible for this rare pain disorder in nine families of different ethnicities in seven countries. Among them are the Mahars in Bird Cove, a 12-hour drive north from St. John's, where at least four members of three related families have been diagnosed, including Owen, now 20, and his brother Joshua, 11.
In a report to be published in the journal Clinical Genetics in April, the researchers list what patients have suffered without suffering -- double hip dislocations, lower-limb amputations, corneal abrasions, burns, stabs, gashes, head trauma and mutilating tongue-biting. A Swiss woman has experienced painless childbirth; one U.S. patient was able to undergo a cystoscopy, a painful exploratory bladder procedure, without anesthetic.
"It is somewhat surprising that one gene has such a profound effect," said study co-author Michael Hayden, co-founder of Xenon and a geneticist at the University of British Columbia. "This tells us that there is a primary target for pain perception that's most profound."
James Henry, a renowned neurophysiologist (not involved in the research) who has studied pain for 30 years, said the unexpected importance of this single gene marks a "monumental turning point in our understanding of pain."
Dr. Henry, scientific director of the Michael G. DeGroote Institute for Pain Research and Care at McMaster University in Hamilton, stressed that drug development is a long road. But for the 20 to 30 per cent of the world's population who suffer chronic pain, he said, "the discovery of this single gene may be a miracle if it can be translated into a new therapy."
To be affected with an indifference to pain, a child has to inherit two defective copies of the SCN9A gene -- one from each parent. Researchers say those who carry a single copy seem to have normal pain sensation and tolerance, which helps to explain the rarity of the disorder. Only in certain pockets of the world have carriers, often distantly related, come together to pass two copies to the next generation.
With so many families descending from small, remote founding populations, Newfoundland has long been a gene hunter's paradise, particularly places like Bird Cove. It hugs the Great Northern Peninsula, a tiny shoreline community where for generations the surnames have been as familiar as the rocks.
But the years have not been kind to Bird Cove with the closing of the cod fishery, and a population of 600 has dwindled to 250, with few jobs and no doctors.
It was to Corner Brook, about 400 kilometres south, that Ms. Mahar, a store clerk, and Mr. Mahar, a logger, sometimes went for medical help when Owen was younger. Elizabeth Ives, then clinical geneticist with Memorial University, first met them there in the mid-nineties. By then Dr. Ives, now retired, had already seen a boy from another Bird Cove family with indifference to pain.
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