DNMT1 and Parkinson disease: Indeed, work by Jowaed et al. [90] reported a reduction in DNA-methyltransferase 1 (DNMT1) in PD patient brains, suggesting that reduced silencing of SNCA is detected in the brains of patients with sporadic PD and that the level of α-synuclein expression is an important determinant of PD pathogenesis [90,91].