PARK9 encodes the transmembrane lysosomal P5-type ATPase ATP13A2, and missense or truncation mutations of PARK9 impair lysosomal function, resulting in autosomal recessive levodopa-responsive early-onset Parkinsonism, also known as Kufor-Rakeb syndrome [100, 101]. The gene discussed is ATP13A2; the disease is Kufor-Rakeb syndrome.