CHCHD2 and Parkinson disease: According to the involvement of different genes, PD can be divided into autosomal dominant forms (PD caused by mutations in SNCA, PARK8, PARK17, PARK21, PARK22, and other genes) and autosomal recessive genetic forms (PD caused by mutations in PARK2, PARK6, PARK7, PARK9, PARK14, PARK15, PARK19, PARK20, PARK23, and other genes) (Schneider and Alcalay, 2017).