TY - JOUR T1 - Late onset Friedreich's disease: clinical features and mapping of mutation to the FRDA locus. JF - Journal of Neurology, Neurosurgery & Psychiatry JO - J Neurol Neurosurg Psychiatry SP - 977 LP - 979 DO - 10.1136/jnnp.57.8.977 VL - 57 IS - 8 AU - G De Michele AU - A Filla AU - F Cavalcanti AU - L Di Maio AU - L Pianese AU - I Castaldo AU - O Calabrese AU - A Monticelli AU - S Varrone AU - G Campanella Y1 - 1994/08/01 UR - http://jnnp.bmj.com/content/57/8/977.abstract N2 - Twenty two patients from 17 families with Friedreich's disease phenotype but with onset ranging from the ages of 21 to 36 are described. Comparison with "typical" Friedreich's disease with onset before 20 years of age showed only a lower occurrence of skeletal deformities. The peripheral and central neurophysiological findings, sural nerve biopsy, and the neuroradiological picture did not allow the differentiation between "late onset" and "typical" Friedreich's disease. Duration of disease from onset to becoming confined to a wheelchair was five years longer in late onset patients. Sixteen patients and 25 healthy members from eight families were typed with the chromosome 9 markers MLS1, MS, and GS4 tightly linked to the FRDA locus. All families showed positive lod scores with a combined value of 5.17 at a recombination fraction of theta = 0.00. It is concluded that "late onset" Friedreich's disease is milder than the "typical" form and that it maps to the same locus on chromosome 9. ER -