Genetic Abnormalities in Friedreich's Ataxia

Abstract
Dürr and colleagues (Oct. 17 issue)1 correlated the phenotypic features of Friedreich's ataxia and the size of an intronic GAA-triplet repeat in the gene that causes the disease, X25, and concluded that “the clinical spectrum of Friedreich's ataxia is broader than previously recognized” and that “the direct molecular test for the GAA expansion on chromosome 9 is useful for diagnosis, determination of prognosis, and genetic counseling.” We disagree with these conclusions.