From LiveScience:
Miniature lab-grown kidneys have been hiding something from the scientists who grew them. Instead of developing into different varieties of kidney cells, some of the cells took a different path and became brain and muscle cells.
These simple mini kidneys — also known as kidney organoids — are grown from stem cells that are encouraged to develop into clusters of specific kidney cells. But it turns out that the "recipes" that encourage the development of specialized kidney cells were also cranking out cells from other organs, according to a new study....MUCH MORE