Definition:

Familial dysautonomia (FD), also known as Riley day syndrome, is an autosomal recessive disorder characterized by developmental arrest in the sensory and autonomic nervous systems. Symptoms include decreased sensitivity to pain and temperature, cardiovascular instability, recurrent pneumonias, and gastrointestinal dysfunction. This disorder is primarily confined to individuals of Ashkenazi Jewish descent, and caused by mutations of the IKAP gene that encodes a scaffolding unit ELP1 for a elongator complex.