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. The gene discussed is TH; the disease is Parkinson disease.