[Molecular genetic diagnosis of Friedreich's ataxia. Ten years experience based on blood sample analysis].

UNLABELLED: Mutations of the frataxin gene give the most common underlying genetic background of recessively inheritable type ataxias in Europe. In our department, we have been establishing the molecular genetic diagnosis of Friedreich's ataxia since 2001. We analyzed a total of 221 blood samples from the whole country.

METHODS

After fragment analysis we performed direct exon sequencing.

RESULTS

This study summarizes the retrospective analysis of these genetic test results. Pathological alteration was identified in altogether 26 cases. 2 expanded alleles were found in intron 1 in all 26 genetically confirmed patients; which is not more than 12% of the total analyzed samples. We did exon sequencing in the case of patients having one expanded allele and found no point mutation in any of the cases.

CONCLUSIONS

In our setting, we could not verify the diagnosis by genetic analysis in a remarkable number of patients, which on one hand underlines the importance of clinical neurologic and clinical genetic analyses before performing tests, and on the other hand, it raises the need to examine the patients for other ataxia types.