We read with interest the article by Dr Cellini and colleagues.1 The authors help define the broad spectrum of neurological signs that occur in carriers of premutation alleles of the fragile X mental retardation 1 (FMR1) gene and make a number of important observations. Most notably, the article documents the importance of testing for the FMR1 premutation carrier state in men older than 50 years of age with sporadic ataxia, finding that the gene abnormality was the cause in almost 5% of cases.
Leehey MA, Hagerman RJ, Hagerman PJ. Fragile X Syndrome vs Fragile X–Associated Tremor/Ataxia Syndrome. Arch Neurol. 2007;64(2):289. doi:10.1001/archneur.64.2.289-a