GBA1 and Parkinson disease: A GWAS performed in 153 Ashkenazi Jewish patients with GBA1-associated Parkinson disease highlighted the gene BIN1 as a potential candidate modifier gene for early-onset GBA1-associated Parkinson disease BIN1 encodes the Bridging Integrator 1 (BIN1) protein, a protein involved in CNS synaptic vesicle endocytosis [78].