AQP4 and fragile X-associated tremor/ataxia syndrome: Table 2 shows the genotype frequency for each SNP according to the presence of FXTAS symptoms. After correction of p-values for multiple comparisons, there was no significant difference in frequencies of any of the analyzed SNPs between FXTAS and no-FXTAS group (Table 3). Adjustment for sex did not change these results (data not shown). Table 4 shows the results of the genotype association analysis between AQP4 polymorphisms and risk of FXTAS, according to different genetic inheritance models.