GBA1 and Parkinson disease: Especially, meta-analyses by the International Parkinson Disease Genomics Consortium et al. (2011), supported the evidence for association of five previously reported risk loci near the genes for alpha-synuclein (SNCA), microtubule associated protein tau (MAPT), cyclin G-associated kinase (GAK), beta-glucocerebrosidase (GBA), and HLA locus (HLA).