Following these landmark reports, a surge of molecular and cellular biological studies describing the physiological functions of the aforementioned gene products (PINK1, LRRK2, Parkin, DJ-1, and α -synuclein) demonstrated that these PD-associated proteins either intrinsically localize to or translocate to mitochondrion, where they regulate various aspects of mitochondrial biology in neurons. Here, SNCA is linked to Parkinson disease.