New Insights Into Human Physiology Involved in Somatic Mosaicism

Induced pluripotent stem (iPS) cell technology involves the generation of pluripotent stem cells from adult somatic cells by the exogenous expression of specific reprogramming factors (see Box). This technology opened the door for us to access a robust platform demonstrating in vitro cellular reprogramming from certain somatic cells to pluripotent status. Recently, Cahan and Daley conducted a bibliometric analysis of the pluripotent stem cells (including iPS cells, embryonic stem [ES] cells, and embryonic carcinoma cells) generated since 2010. They found that the number of publications concerning ES cells has decreased, whereas the number of publications concerning the applications of pluripotent stem cells has increased. They pointed out that it is the increase in the studies of iPS cells that brought about this change in the research trend, because it gave scientists access to pluripotent stem cells with robust and reproducible technology. As Cahan and Daley have shown, iPS cells quickly became recognized as an innovative research tool for the study of biology and medicine. In this review, we focus on iPS cell technology, with a special emphasis on its cloning event, which is essential for the reprogramming process, and discuss perspectives related to the creation of in vitro models of human physiological conditions, including complex diseases. Review