A multi-centre clinico-genetic analysis of the VPS35 gene in Parkinson disease indicates reduced penetrance for disease-associated variants - Sharma,M; Ioannidis,JPA; Aasly,JO; Annesi,G; Brice,A; Bertram,L; Bozi,M; Barcikowska,M; Crosiers,D; Clarke,CE; Facheris,MF; Farrer,M; et al. (JOURNAL OF MEDICAL GENETICS, 2012)