SLC1A3

Episodic ataxia

Several variants (also called mutations) in the SLC1A3 gene have been found to cause episodic ataxia type 6 (EA6), which is a nervous system disorder involving episodes of poor coordination and balance (ataxia).

The variants that cause episodic ataxia change single protein building blocks (amino acids) in the EAAT1 protein. Research shows that the altered EAAT1 proteins allow more chloride ions to flow in or out of cells than usual. Researchers suspect that glia with these altered channels cannot maintain the correct volume or ion balance, causing them to shrink and die.

The loss of glia is thought to impair the clearance of glutamate from between neurons in the brain. The excess glutamate may overexcite certain neurons, disrupting normal communication between these cells. The changes in signaling between neurons likely causes the episodes of uncoordinated movement seen in people with episodic ataxia.