SLC1A6 and spinocerebellar ataxia type 5: A similar situation has been observed for the Purkinje cell glutamate transporter EAAT4, where an in-frame deletion in the third spectrin repeat identified from the Lincoln SCA5 pedigree disrupted stabilization of EAAT4 at the cell surface compared with wild-type β-III spectrin (17), even though EAAT4 interacts with the unaffected C-terminus of β-III spectrin (28).