LRRK2 and Parkinson disease: Overexpression of autosomal dominant mutant genes such as SNCA (A53T, A30P α-syn) and LRRK2 (leucine rich repeat kinase 2) (G2019S, R1441C) is induced to replicate familiar PD [39], whereas knockout, knockin, or knockdown of autosomal recessive genes such as Parkin, DJ-1, and PINK1 is also performed in rodents to replicate other familiar PD.