Quantitative Real-Time PCR (qRT-PCR) and western blot assay showed that the expression levels of LRRK2 were increased, and the miR-205-5p level was decreased in the midbrains of PD mice (Chen et al., 2018), which suggested that downregulated miR-205 probably contribute to the increased LRRK2 protein level in the brains of patients with sporadic PD. The gene discussed is LRRK2; the disease is Parkinson disease.