Studies have found decreased levels of plasmalogens in the brain and blood of patients with PD, and treatment with the DHA-plasmalogen precursor PPI-1011 improved plasmalogen levels and reversed loss of striatal dopamine markers (dopamine, dopamine transporter, vesicular monoamine transporter-2) in a MPTP-treated mouse model of PD (Miville-Godbout et al., 2016; Dragonas et al., 2009). This evidence concerns the gene SLC6A3 and Parkinson disease.