British scientists have now taken cells from a mouse embryo and, "flipped a genetic switch" in the DNA, and then injected the product into another mouse with a defective organ, where those injected cells grew into the whole organ of another mouse. (In that case, it was the thymus, which relates to the immune system.)
The work was done under the lead of Prof. Clare Blackburn, of the Medical Research Council / Center for Regenerative Medicine at the University of Edinburgh. The most complete article I've found is by Rebecca Smith, medical editor of London's Daily Telegraph. Here's the link
You can also find a shorter piece by Pranav Dixit in Gizmodo. Here's that link
If you've keeping up with this blog, you'll have seen other stories about growing replacement organs. So what's distinctive about this? This is reportedly the first time the organ has been grown inside the target creature.
When can we expect to find something like this happening for humans? According to one scientist, maybe ten years and tens of millions of pounds for research. But by then, odds are the products will relate to other elements in the quest for radical life extension.