SNCA and Mental deterioration: Seven of the eight genes (GAK, TMEM175, SNCA, PLEKHM1, CRHR1, MAPT and NSF) have been implicated via GWAS by others as having individual SNPs associated with PD risk, whereas a joint effect of two SNPs at chromosome 7p15.3 (rs2965400 and rs6461595, p = 3.77 × 10−6) within an intron of the DNAH11 gene has not previously been implicated in PD, although it has been reported to be associated with cholesterol level and (age-related) cognitive decline.