PLEKHM1 and Parkinson disease: Therefore, we investigated the influence of both the MAPT haplotype and the PD status on mRNA expression levels of MAPT, MAPT-AS1, STH, PLEKHM1 and NSF within the MAPT locus as well as the alpha-, beta-, gamma-synuclein genes SNCA, SNCB, SNCG. In addition, we examined protein levels of soluble and insoluble tau and α-syn under the same paradigm.