Dissecting the Phenotype and Genotype of PLA2G6-Related Parkinsonism.

Background Complex parkinsonism is the commonest phenotype in late-onset PLA2G6-associated neurodegeneration. Objectives The aim of this study was to deeply characterize phenogenotypically PLA2G6-related parkinsonism in the largest cohort ever reported. Methods We report 14 new cases of PLA2G6-related parkinsonism and perform a systematic literature review. Results PLA2G6-related parkinsonism shows a fairly distinct phenotype based on 86 cases from 68 pedigrees. Young onset (median age, 23.0 years) with parkinsonism/dystonia, gait/balance, and/or psychiatric/cognitive symptoms were common presenting features. Dystonia occurred in 69.4%, pyramidal signs in 77.2%, myoclonus in 65.2%, and cere…