Young-onset Parkinson’s (YOPD) accounts for 10% of all Parkinson’s. Some cases are associated with known genetic mutations, but most are not. Laperle and others used stem cells from individuals with YOPD without any known gene mutations including PD genes EIFG1, PARK2, LRRK2, GBA, SNCA, PINK1, PARK7, VSP35 and ATP13A2 or amplifications of the SNCA locus to grow functional dopamine secreting neurons. Even in the absence of known genetic mutations newly grown dopamine neurons showed increased accumulation of α-synuclein and other Parkinson’s signature pathologies. The α-synuclein accumulation was reduced with activation of proteasome enzymes or phorbol esters. This study shows that induced pluripotent stem cell modeling is promising in growing dopamine neurons. However, there are other unknown genetic contributions to this condition. In addition, they have raised another possible treatment solution to YOPD which is photbol esters, but much research is needed in the area.