Interestingly, in our previous studies on post-mortem laser-microdissected DA neurons, we observed a reduction of DICER1 gene expression in PD patients (–1.9 fold, P<0.05) compared with age-matched healthy individuals, which was even more pronounced in the male population (–2.7 fold, P<0.05).32 Here, DICER1 is linked to Parkinson disease.