SCN9A Gene for Pain

Six children from three related Pakistani families feel no physical pain and don’t know when they’re harming themselves. Although capable of feeling other sensations like warm and cold, their lack of pain perception have put them in harm’s way.

• All six have had lip injuries, some so severe they required plastic surgery
• Two lost one-third of their tongues
• Most suffered fractures or bone infections
• Some have been scalded by boiling liquids or steam
• Others burned from sitting on radiators

Another relative with the same condition became a street performer who specialized in piercings and other painful stunts. He later died after jumping off the roof of a house.

A common mutation in the SCN9A gene, which is expressed in nerve cells, has been identified in these six children.

The SCN9A gene encodes a ’sodium channel’: one of the structures that allows electrical charge to flow into nerve cells, triggering a signal, the researchers explain. Without this particular type of sodium channel, the brain does not receive any signal that the body has encountered a pain-causing stimulus.

The identification of SCN9A may lead to new treatments for the severe pain that often accompanies other debilitating illnesses.

Washington Post, December 13, 2006
news @ nature.com, December 13, 2006
Photo credit: slapjack

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