Amino acids are essential building blocks of all mammalian cells. In addition to their role in protein synthesis, amino acids play an important role as energy fuels, as precursors for a variety of metabolites and as signaling molecules. Disorders associated with the malfunction of amino acid transporters reflect the variety of roles fulfilled by these proteins in human physiology. Mutations of brain amino acid transporters affect neuronal excitability. Mutations of renal and intestinal amino acid transporters affect whole-body homoeostasis, resulting in malabsorption and renal problems. Amino acid transporters that are integral parts of metabolic pathways when mutated alter their normal function giving rise to a variety of metabolic diseases.

Along the last 20 years, mutations in amino acid transporter genes causing rare inherited diseases have been identified, and the search for new transporters involved in rare diseases continues. The human genome contains eleven gene families coding for more than 50 amino acid transporters. Disease-causing mutations have already been identified in one third of the amino acid transporters. Moreover, it is likely that other amino acid transporters will prove being involved in rare inherited diseases.

The identification and study of disease causing mutations has facilitated the discovery of yet unknown aspects of transporter physiology, of the pathogenic mechanisms involved, and on the therapeutics side, the development of screening programs in newborns and new therapies.

The Fundación Ramón Areces Symposium on Amino acid transport defects is focused in rare diseases with behavioral, sensitive, immunological and metabolic manifestations. Symposium sessions will be devoted to glutamate and glycine transporters, heteromeric amino acid transporters and mitochondrial transporters of amino acids. Selected talks will present state of the art knowledge on the structure of these transporters and animal models instrumental to reveal the pathogenic mechanisms of the related diseases. Finally, new potential therapies based on etiology studies will be also presented.