GBA1 and dementia: This prompted the study of AAV9‐mediated delivery of a functional glucocerebrosidase transgene (GCase) to a mouse model of nGD,19 which is caused by GBA1 mutations encoding for β‐glucocerebrosidase, an enzyme associated with lysosomal and cell membranes, and resulting in impaired β‐glucocerebrosidase activity and neurotoxicity from glucocerebroside accumulation in macrophages and microglia,101, 102, 103 causing progressive neuroinflammation, neuronal loss, cerebellar ataxia, dementia, epilepsy, and paralysis.