Familial dysautonomia (FD) is a rare, progressive, recessive genetic disorder of the autonomic nervous system seen primarily in people of Eastern European Jewish descent that affects the development and survival of sensory, sympathetic and some parasympathetic neurons in the autonomic and sensory nervous system.
FD results in variable symptoms, including insensitivity to pain, inability to produce tears, poor growth and labile blood pressure (episodic hypertension and postural hypotension). [Source: Wikipedia 
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