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Induced pluripotent stem cells (iPS cells) obtained by repro-gramming of adult human fibroblasts1,2 are currently being used to develop models of a wide range of neurological diseases including spinal muscular atrophy, ALS, Parkinson disease and schizophrenia. Such cellular models will serve as valuable tools for understanding disease pathogenesis and progression.3-5 The extent of genetic and epigenetic reprogramming and the mecha-nism for induction of pluripotency remains to be elucidated.6-11 Nevertheless, the iPS technology has progressively been refined and human iPS cells can now be generated from different cell sources using methods that no longer rely on viral vectors or transgene integration.12-16 These technical advancements have made iPS-derived neurons more suitable for replacement therapy, although they are still associated with substantial risk for tumor formation.16-1