A method to isolate rare human pluripotent stem cells with precisely engineered mutations is described in a paper published this week in Nature Methods. This method will enable the simple generation of human iPS cell lines with precise disease mutations or reversal of disease mutations, which will help advance our understanding of the genetic basis of disease.
A vast number of genomic mutations have been statistically associated with human disease, and methods are sorely needed to experimentally study the biological effects of these mutations. The use of targeted genome engineering tools to make precise mutations in human pluripotent stem cells offers an exciting route towards this goal.
But making precise genomic changes in a way that otherwise minimally perturbs the genome is very laborious. Bruce Conklin and colleagues adapt methods classically used in yeast genetics for human induced pluripotent stem (iPS) cells. They combine their approach with sensitive digital biochemical detection and show that it can be used to isolate rare human iPS cells in which precise mutations have been generated in the desired gene using low levels of TALENs (transcription activator-like effector nucleases). They demonstrate the approach on multiple genes in the human genome.