While it is critical to Ca2+-dependent exocytosis (72), its exact physiological role still is subject to further research, and deficiencies in the expression of SV2A have been described in a growing number of neurodegenerative disorders, including frontotemporal dementia (FTD), Parkinson's Disease (PD), Alzheimer's disease (AD), corticobasal degeneration (73–77), as well as further neurological conditions, such as epilepsy (78–80), where it has been identified as the binding site for the antiepileptic drug levetiracetam (81). This evidence concerns the gene SV2A and Parkinson disease.