描述
Both the infantile and Finnish (Salla disease; 604369) forms of sialuria are due to mutation in the SLC17A5 gene, which encodes a vesicular excitatory amino acid transporter (VEAT) with dual physiologic functions. When present in synaptic vesicles in the central nervous system, sialin is responsible for vesicular storage and subsequent exocytosis of aspartate and glutamate. When present in lysosomes, it acts as an H+-coupled sialic acid exporter. Mutations in this transporter cause accumulation of free sialic acid in the urine. Symptoms include seizures, mental, growth, and motor retardation, nystagmus, and speech development.