Familial Dysautonomia

 

Pain is a warning sign that something is wrong.   It tells us when we have to move around to restore blood flow, when we have been overworking ourselves and need to give our muscles a break, or when we’ve been injured and need help.  People born with familial dysautonomia do not feel pain; they don’t have pain fibers when they’re born.  People with this disease run into problems such as the eye becomes dry and eroded because there is no signal to blink, teeth cut the tongue and cheeks, and joints wear out because there is no signal to tell the individual when to take it easy.

Familial dysautonomia, or FD, is a disorder of the autonomic nervous system which affects the development and survival of sensory, sympathetic, and some parasympathetic neurons in the autonomic and sensory nervous system resulting in various symptoms including: insensitivity to pain, inability to produce tears, poor growth, and labile blood pressure.  People with FD have frequent vomiting crises, pneumonia, problems with speech and movement, difficulty swallowing, inappropriate perception of heat, pain, and taste, as well as unstable blood pressure.  But, FD does not affect intelligence.

Familial Dysautonomia is a genetic mutation on chromosome 9 that is recessive.  Because the genetic mutation is on a specific section of chromosome 9, it causes the DNA of the chromosome to be altered so that the cells in the afflicted individual’s body do not function properly.  The cells do not have complete functioning ability, in other words, some of the normal functioning activities, such as the response to pain, do not occur.  The reason this disorder is so incredibly rare is because the parents must both contain the same mutated gene and the child must be in the 25% that receives both of the recessive genes.  So, both of the parents must be in the extremely rare population of having the same mutated gene, and must pass on both of the recessive genes to the offspring.  This is why it is so difficult to determine who is at risk for this disorder because the parents often exhibit no symptoms of the disorder, and often have no clue they are carriers.  The parents may also have other children who are unaffected by the disorder, because the child has a 75% chance of being born without the disorder.