FMR1 and fragile X-associated tremor/ataxia syndrome: The current study therefore aims to: (1) estimate the prevalence of MCP and pallidal T2-abnormalities in men with normal and premutation FMR1 alleles; (2) examine the relationships among MCP and pallidal T2-abnormalities, FXTAS symptoms, and iron content in the cerebellar dentate nucleus and globus pallidus; and (3) investigate the associations among MRI findings (i.e., T2-abnormalities and iron content) and FMR1 molecular markers (i.e., CGG repeat length and mRNA level).