Objective: To explore the clinical and genetic characteristics of patients with dentatorubro-pallidoluysian atrophy (DRPLA).
Methods: DNA analysis for DRPLA gene was performed in two patients. Clinical features and genetic testing of Chinese DRPLA patients reported in the literature were reviewed in terms of initial symptoms, CAG repeat and age of onset.
Results: Both families were confirmed by genetic analysis. In family 1, the number of CAG repeat in the proband, his brother and his mother was determined respectively as 8/65, 8/53 and 8/18. In family 2, the number of CAG repeat was respectively 13/63, 13/18, 18/52 and 13/13 in the proband, his brother, his father and his mother. The size of the expanded CAG repeats has inversely correlated with the age at onset (P<0.05, r=- 0.555). The age at onset of epilepsy was 10 and that for the onset of ataxia is forty years in initial symptom.
Conclusion: The clinical characteristics of DRPLA include epilepsy, ataxia and cognitive impairment. The initial symptoms are epilepsy in adolescence and ataxia in adults. The size of expanded CAG repeats inversely correlates with the age at onset. The initial symptoms are different with different age of onset. It is difficult to diagnose DRPLA at an early stage.