FMR1 and fragile X-associated tremor/ataxia syndrome: In contrast, we observed a decrease in FMRP levels in the two of the three FXTAS patients tested, consistent with published results (Ludwig et al., 2014; Pretto et al., 2014), and found increased cerebellar levels of APP in these same FXTAS patients, suggesting an impact of lower FMRP on APP expression in humans.