Multiple analyses resulted in four significant genes: proteasome (prosome, macropain) subunit-alpha type-2 (PSMA2; p = 0.0002, OR = 1.15 95% CI 1.07-1.24), laminin, beta-2 (laminin S) (LAMB2; p = 0.0078, OR = 2.26 95% CI 1.24-4.14), aldehyde dehydrogenase 1 family-member A1 (ALDH1A1; p = 0.016, OR = 1.05 95% CI 1.01-1.1), and histone cluster-1 H3e (HIST1H3E; p = 0.03, OR = 0.975 95% CI 0.953-0.998) differentiating between medicated PD subjects versus controls.
Twelve genes altered in similar manner in AD and PD, while four genes showed differential expression profiles between AD and PD in different brain regions (cannabinoid-receptor-2, Histone-cluster-1-H3e, nicotinic-cholinergic-receptor-alpha6 and beta-site-APP-cleaving enzyme-1).