Khodr et al. [63] tested the effect of mir30-hSNCA delivered by AAV2/8 in a rat model and noticed that the silencing of the SNCA gene caused by this miRNA protected against the deficit in the forelimb and decreased the loss of tyrosine hydroxylase-immunoreactive (TH-IR) neurons in the substantia nigra (SN), but unfortunately negative outcomes like toxic effects in the striata, absence of total protection of TH-IR and swelling in the SN were noticed, and hence the idea of using the dose applied in this experiment for clinical PD therapeutics was dropped. This evidence concerns the gene SNCA and Parkinson disease.