To investigate the association of AQP4 SNPs with the risk of presenting FXTAS, a total of seven common AQP4 SNPs were selected and genotyped in 95 FMR1 premutation carriers with FXTAS and in 65 FMR1 premutation carriers without FXTAS. This evidence concerns the gene AQP4 and fragile X-associated tremor/ataxia syndrome.