LRRK2 and Young adult-onset Parkinsonism: Scientifics have identified at least 13 gene mutations, among which one could highlight those in the genes SNCA (synuclein, alpha non-A4 component of amyloid precursor), PARK2 (Parkinson's disease autosomal recessive, juvenile 2), PARK7 (Parkinson's disease autosomal recessive, early-onset 7), PINK1 (PTEN-induced putative kinase 1), and LRRK2 (leucine-rich repeat kinase 2) [15].