© BRYAN SATALINOThe past decade has seen the birth of two incredibly useful biological tools, and now scientists are beginning to marry them. The first is human induced pluripotent stem cells (iPSCs). Nobel Prize–winning advances, beginning with mice in 2006 and subsequently in humans, showed that it was possible to revert adult skin cells to pluripotent stem cells, which can in turn be coaxed to become nearly any cell type. These cells are the cell-scale embodiment of a person’s genome, and provide researchers with the ability to create cell types that would be otherwise impossible to cull from the living body. iPSCs offer powerful new ways to model monogenetic and complex human diseases and to tailor cell-based therapies.
The second tool is the CRISPR-Cas9 system, which allows easy and precise editing of any region of the genome. When it comes to traditional immortalized cell lines, such as HeLa or HEK293, cutting with CRISPR is something a relative newcomer can learn in week. A second wave of CRISPR-based methods that work by boosting or dampening gene-expression levels, rather than cutting genes, has made the tool even more useful.
Together, these techniques are more than the sum of their parts. CRISPR’ing human iPSCs allows researchers to manipulate genes to study their functions in the context of specific diseases, or to correct genetic defects in patient cells. One challenge that seamless gene editing helps address is the genetic variability across different iPSC lines that has prevented ...
