Studies of rare large families showing classical Mendelian inherited PD have allowed for the identification of 11 genes out of 16 identified disease loci. They include dominant mutations in Leucine-rich repeat kinase 2 (LRRK2), recessive mutations in Parkin (coded by PARK2) and PTEN-induced putative kinase (PINK1) [6], as well as both rare dominant mutations and multiplications in the gene encoding α-synuclein (SNCA). The gene discussed is PINK1; the disease is Parkinson disease.