Furthermore, we have reported that GBA1 variants pathogenic for Gaucher disease are also significantly, albeit with a small odds ratio, associated with an increased risk of developing multiple system atrophy (MSA), which is also a neurodegenerative disorder characterized by various combinations of autonomic failure, parkinsonism, and cerebellar ataxia along with the accumulation of α-synuclein within oligodendroglia [10]. Here, GBA1 is linked to Parkinson disease.