The neuroprotective role of Hsp70 in the pathogenesis of PD is highlighted by a genetic screening of Drosophila PD model, which identified Hsp70 and Hsp40 as two major suppressors of the neurotoxicity caused by mHTT (Kazemi-Esfarjani and Benzer, 2000). Here, HSPA4 is linked to Parkinson disease.