A life without pain­-a congenital disease caused by a newly discovered mutation

Norrbottnian congenital insensitivity to pain, a disease that brings complete insensitivity even to injuries that cause severe pain in healthy people, is caused by a mutation in a gene on chromosome 1. This has been shown in a dissertation by Jan Minde at Umeå University in Sweden.

A life without pain may be thought to be desirable and is no doubt seen by many as an ideal existence. But pain is the body’s way of warning us of impending injury and is thus an important defense mechanism in daily life. Parents of children with congenital insensitivity to pain face many difficult situations and decisions.

The personnel at the orthopedic clinic at Gällivare Hospital have worked with a few children with this disease.

The mother of a little boy was horrified when she discovered that her son experienced no pain whatsoever when he fell from the second story of the house. Later when the child painlessly broke his shin bone, he amused himself by lifting his leg, creating an abrupt, abnormal angle in his leg that scared everyone who saw it.

A grade-school girl jumped from chairs to the floor, landing on her knees, painlessly producing a cracking sound, to her delight. We rely on pain to teach us how to master our complicated environment.

The disorder is caused by a mutation in a gene for nerve growth factor beta. The mutation keeps the nerve system from developing normally, producing hardly any nerve fibers to transmit pain and temperature (hot and cold) to the brain. The mutation is on chromosome number 1.

The research team that Jan Minde belongs to at Umeå University in Sweden has diagnosed a variant of the disease in a large extended family in Norrbotten (North Bothnia) province. They call the disorder Norrbottnian congenital insensitivity to pain.

Thus far three patients have been diagnosed with the mutation on both copies of the gene. These patients are affected by the ailment at a very tender age. It is a hereditary nerve disorder that primarily affects the joints of the lower extremities in the form of severe malpositioning. It is important for these children to be informed of the problem and for them to learn to protect their joints, and they may also need splints and bandages. Surgery may be necessary to rigidify joints, but joint prosthetics do not work for individuals who feel no pain to protect their joints. The dissertation also describes the microscopic alterations in the nerves.

Some 30 adults have also been diagnosed with the mutation in only one copy of the gene. They develop a milder form of the disorder that occurs in adulthood.