Both reported a good response with substantial improvement of UPDRS-III scores and reduction of LEDD postoperatively, and only slight to moderate decline in cognitive function after one and 3 years, respectively, in line with overall STN-DBS results in PD.50,51 A third case report describe a patient with a mosaicism of SNCA duplication show an overall good outcome of DBS, where GPi was chosen as target due to prominent dyskinesias and mild cognitive impairment.15 The gene discussed is GPI; the disease is Parkinson disease.