Editing Human cloning (section)

===Induced pluripotent stem cells (iPSCs)===
{{Main|Induced pluripotent stem cell}}
[[File:Overview of iPS cells.png|thumb|upright=1.25|Overview of iPS cells]]

Creating induced [[Pluripotency|pluripotent]] [[stem cell]]s ("iPSCs") is a long and inefficient process. [[cell potency|Pluripotency]] refers to a stem cell that has the potential to [[cellular differentiation|differentiate]] into any of the three [[germ layers]]: [[endoderm]] (interior stomach lining, gastrointestinal tract, the lungs), [[mesoderm]] (muscle, bone, blood, urogenital), or [[ectoderm]] (epidermal tissues and nervous tissue).<ref name=Binder>{{cite book|editor-last1= Binder| editor-first1= Marc D.|title=Encyclopedia of Neuroscience|year=2009|publisher=Springer|location=Berlin|isbn=978-3540237358|edition=online|editor-last2=Hirokawa| editor-first2= Nobutaka| editor-first3= Uwe |editor-last3= Windhorst}}</ref> A specific set of genes, often called "reprogramming factors", are introduced into a specific adult cell type. These factors send [[cell signalling|signals]] in the mature cell that cause the cell to become a pluripotent stem cell. This process is highly studied and new techniques are being discovered frequently on how to improve this induction process.

Depending on the method used, reprogramming of adult cells into iPSCs for [[Implantation (human embryo)|implantation]] could have severe limitations in humans. If a virus is used as a reprogramming factor for the cell, cancer-causing genes called [[oncogenes]] may be [[regulation of gene expression|activated]]. These cells would appear as rapidly dividing cancer cells that do not respond to the body's natural cell signaling process. However, in 2008 scientists discovered a technique that could remove the presence of these oncogenes after pluripotency induction, thereby increasing the potential use of iPSC in humans.<ref name="Cancer threat removed">{{cite news |url=http://www.latimes.com/news/nationworld/nation/la-sci-stemcell6-2009mar06,0,63456.story |title=Cancer threat removed from stem cells, scientists say |newspaper=Los Angeles Times |first=Karen |last=Kaplan |date=6 March 2009 |access-date=15 April 2014 |archive-date=10 March 2009 |archive-url=https://web.archive.org/web/20090310085937/http://www.latimes.com/news/nationworld/nation/la-sci-stemcell6-2009mar06,0,63456.story |url-status=live }}</ref>