Reduced levels of lysosomal proteins (e.g. LAMP1 and LAMP2A) or molecular chaperones such as certain heat-shock family proteins support autophagy dysfunction in idiopathic PD [120], while mutations in genes such as GBA1 which reduces activity of the lysosomal enzyme GBA [121] and PARK2 or PARK6 which are known to impair autophagy [100] support the involvement of the autophagy lysosomal system in the pathogenesis of familial PD case. The gene discussed is GBA1; the disease is Parkinson disease.