GBA1 and Parkinson disease: We confirm previous reports suggesting that GBA variants can influence the motor phenotype of patients with PD.32 Those with GBA mutations in our study were at a more advanced Hoehn and Yahr stage, even when adjusted for disease duration, compared with non-carriers, which is consistent with previous reports.11 However, the UPDRS motor scores in our study were not significantly different between the groups, although all our patients were assessed ‘on’ medication.