GBA1 and Parkinson disease: Genetic factors are also important in the development of PD, with key genes such as leucine-rich repeat kinase 2 (LRRK2), the alpha-synuclein gene (SNCA), Parkin, DJ-1, PTEN-induced kinase 1 (PINK1), and glucocerebrosidase (GBA) being major contributors to its pathogenesis [4].