The ability to reprogram adult skin fibroblast into induced pluripotent stem cells (iPSCs) provides a source of unlimited cells genetically matched to a patient. Beside the therapeutic applications within regenerative medicine field, these cells have an exiting potential for basic research for the in vitro modeling of diseases. However, modeling of late onset disorders such as Alzheimer’s (AD) or Parkinson (PD) by conventional differentiation paradigms remains a challenge, as current iPSC differentiation protocols yield cells that typically show the “age” of fetal-stage cells. My main objective is to be able to recreate a late onset disease phenotype such AD or PD by accelerating aging in vitro. Based on the premature aging syndromes associated to mutation in telomerase components, I want to explore the effect of telomerase down regulation in human iPSC prior or during neural differentiation.