Abstract
The aim of research is to present clinico-genetic characteristics of Huntington's disease in a representative sample of Czech population, and to show the benefit of genetic testing and its difficulties. Huntington's disease (HD) is an autosomally dominant hereditary neurodegenerative disease with its onset in adulthood conditioned by the expansion of CAG repetition in the coding area of gene IT 15.
Since 1994, there have been carried out 629 genetic tests: 567 diagnostic, 61 presymptomatic and one prenatal tests. The diagnostic test confirmed the clinical diagnosis of HD in 72.5 % patients.
A new mutation was demonstrated in two cases. With positive familial history, the diagnosis was confirmed in 95 % patients, in the absent familial occurrence the test was positive in 18 % patients, in the case of unclear anamnestic data HD was the problem in 60 %.
That has shown the benefit of DNA analysis as a masterful tool in differential diagnostics. The presymptomatic test was completed by about 1/3 of applicants in the risk of HD development.
The result was positive in 40 %. The acceptance of presymptomatic test made 4 % of supposed risky population, prenatal diagnostics was required quite exceptionally.
The low utilization of predictive test is caused by the discrepancy between the possibility of precise molecular-genetic diagnostics and non-existence of an effective therapy for HD.