İnce Dilek GÜNAL, Meliha GÜLERYÜZ, Sevinç AKTAN

TRINUCLEOTIDE REPEAT LENGTH AND CLINICAL PROGRESSION IN HUNTINGTON'S DISEASE

Objective: Huntington's Disease is a progressivedegenerative disorder having an expanded triplicaterepeat in the gene IT-15 on chromosome 4. Theinterrelation between the trinucleotide repeat lengthand disease progression was studied.Methods: Five patients included in the study wereevaluated by "Quantified staging of functional capacityfor Huntington's Disease patients” and age of diseaseonsets were determined. Progression rate wascalculated and interrelationship between age ofdisease onset and repeat length; progression rate andrepeat length were studied.Results: We found a statistically significant negativecorrelation between age of disease onset andtrinucleotide repeat length (pearson r=-0.9514p<0.05). There was a statistically significant positivecorrelation between CAG repeat length andprogression rate (pearson r=0.8809, p<0.05).Conclusion: Our study, conducted with a very limitednumber of patients, revealed the correlation betweentrinucleotide repeat length and disease progression.It like few similar studies in the literature, gave animpression of the important pathophysiological role ofexpanded CAG repeat during the entire course of thedisease.Key Words: Huntington's Disease, progressionrate, trinucleotide repeat, prognosis.

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