Parkin mutations and phenotypic features in Czech patients with early-onset Parkinson's disease.

ABSTRACT

OBJECTIVES: Mutations in several genes such as parkin can be detected in up to 20% of patients with early-onset Parkinson's disease (EOPD). The aim of our study was to determine the frequency of parkin alterations and phenotypic characteristics in Czech EOPD patients. METHODS: A total of 45 EOPD individuals (age at onset <45 years) were phenotyped and screened for parkin mutations. RESULTS: In total, 19 patients (42.2%) were carriers of previously described heterozygous genetic alterations. Parkin mutations (Ex2del, R402C) were identified in two (4.4%) cases, non-pathogenic variant A82E plus polymorphism D394N occurred in one (2.2%) patient and parkin polymorphisms (3x S167N, 1x R334C, 7x V380L, 4x D394N) were found in 15 (34.9%) individuals. Furthermore, the G2019S mutation in the LRRK2 gene was found in one (2.2%) subject. CONCLUSION: The clinical characteristics of our patients correspond to previous descriptions of EOPD phenotype. This is the first report on EOPD-associated genetic alterations among Czech patients. Our results support the hypothesis that single heterozygous parkin variants may act as risk factors for EOPD.