The limited experimental access to disease-affected human tissues has severely impeded the elucidating of molecular mechanisms underlying disease development. Generation of induced pluripotent stem cells (iPSCs) by over-expression of defined transcription factors in somatic cells, in particular in those from patient somatic cells, presents an attractive and promising approach to model the early stages of diseases in vitro and to screen novel biomarkers as well as therapeutic medicines. Recently, many research groups have independently reported that patient-specific iPSC-derived cells recapitulated multiple features of pathological events of a particular disease, offering experimental evidence of utilizing patient-specific iPSCs to model diseases and reevaluate the current therapies. We have derived iPSC lines using somatic cells of patients suffering from Klinefelter's Syndrome (KS) and Alzheimer's Disease (AD) and explored the possibility to use these iPSC lines to recapitulate the pathological features of the diseases. Our results show that patient's specific iPSC lines provide good opportunity to study the development and treatment of diseases.