With this in mind, no significant differences were identified in the GAUCHERITE cohort, between plasma gpNMB concentrations in patients with idiopathic Parkinson’s disease and Parkinson’s disease in GBA1 heterozygotes relative to healthy control subjects; indeed the only group criterion for defining a statistically raised plasma concentration was individuals with a diagnosis of Gaucher disease. Here, GPNMB is linked to Gaucher disease.