By using CRISPR-Cas9, coupled to the DNA-methyltransferase 3A catalytic domain (DNMT3A), Kantor et al. [48] decreased SNCA mRNA and protein in human induced pluripotent stem cell (hiPSC)-derived DNs from a PD patient with the triplication of the SNCA locus. Here, DNMT3A is linked to Parkinson disease.