Excitatory amino-acid transporter 4 (EAAT4) is a protein that in humans is encoded by the SLC1A6 gene.It is a member of the high-affinity glutamate and neutral amino acid-transporter family. It transports L-glutamate and also L- and D-aspartate predominantly in the cerebellar cortex. Genetic polymorphism in the SLC1A6 gene is suggested to be refered to glutamatergic dysfunction in schizophrenia pathogenesis.