MECP2 and Rett syndrome: In the present paper we have followed through on this approach to interrogate disease associated genotypes in a physiological context by first generating isogenic iPSCs containing a targeted gene mutation mimicking PD (SNCA A53T Homozygous (HO), NCL (GRN R493X Homozygous (HO)) and Rett Syndrome (MECP2 Hemizygous Truncation (HM) knockout (KO).