When the presence of dyskinesia and dystonia was controlled for the presence of PARKIN homozygous/compound heterozygous or LRRK2 mutations, the result for dyskinesia remained significant [dyskinesia: p = 0.007, OR 4.37 (95%CI 1.49–12.85)], but it became non-significant for dystonia (p = 0.088). This evidence concerns the gene PRKN and drug-induced dyskinesia.