GBA1 and Parkinson disease: These are the most common GBA1 variants in The Netherlands.27 These variants are associated with Parkinson’s disease but not with Gaucher’s disease and normally present with a milder phenotype than other GBA1 mutations associated with Parkinson’s disease.36 The prevalence of these variants in our cohort might explain why we did not find differences in the age of onset between Parkinson’s patients with and without GBA1 mutations.1,37 Early age of disease onset is mainly observed in carriers of severe GBA1 variants.10,38