Familial dysautonomia (Riley-Day syndrome): When baroreceptor feedback fails

Familial dysautonomia (FD) is a rare hereditary disorder caused by mutations within the gene that encodes for I-kappa-B kinase complex associated protein (IKAP). A deficiency of IKAP affects the development of primary sensory neurons including those carrying baroreflex afferent volleys, a feature that explains their characteristic sensory loss and labile blood pressure. This review describes the history, the genotype of FD and the un-usual cardiovascular autonomic phenotype of these patients. We outline the main consequences of a failure to receive information from arterial baroreceptors, including the characteristic autonomic storms and severe end-organ target damage. (C) 2012 Elsevier B.V. All rights reserved.