Wired News: Neurons Derived From Stem Cells

yes we can dreate all sorts with this, but is it the mix of chemicals and the timing, or the conscious choice that makes it???

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Wired News: Neurons Derived From Stem Cells: "The conclusion, reported in the science journal Nature Biotechnology, is important for two reasons. First, stem-cell scientists have struggled to accomplish what researcher Su-Chun Zhang and his colleagues have just accomplished. It took Zhang's team two years of tedious trial-and-error experiments to direct stem cells to turn into motor neurons.
Perhaps more important, Zhang's recipe shows researchers that timing is everything when adding their chemical cocktails to stem-cell stews. Stem cells are vulnerable to successful human manipulation for only the briefest of moments -- and at different intervals depending on the results each researcher craves.

'This shows that you can't dump whatever growth factors you want in there,' Zhang said. 'It's not that simple. It's very specific. You have to have the right cocktail in the right amount at the right time.'


But with Zhang and others showing that the biological clock ticks differently in different animals and in each type of cell, it appears translating animal data to human terms is more about timing than biology.

"That is also somewhat reassuring," said Isacson, who has created dopamine-producing brain cells from stem cells. Parkinson disease patients lose dopamine cells, which help regulate body movement.

Embryonic stem cells are created in the first days after conception and ultimately turn into the 220 or so types of cells that make up the human body. Scientists believe they can someday control what stem cells become and when, using that power to replace damaged and dead cells that cause a wide range of suffering, from diabetes to Parkinson's.

But harnessing that power has proved elusive in all but a few cell types such as heart and two other types of brain cells.

'This is an important contribution because stem cell biology is difficult," Isacson said. "It helps decode the locks.'"