August 23, 2013

Synthetic DNA circuits inserted into human stem cells could soon allow us to build new organs with unprecedented precision and speed. The circuits can be designed on a computer and assembled from ready-made parts ordered online. The technique could prove an efficient way of making organs for transplant without the worry of rejection, and raises the tantalising possibility that it might one day be possible to upgrade the organs we were born with. Human cells have already been used to create a tiny liver and a set of neurons.

"At the moment, the aim is to normalise cells, but in future, enhancement has to be on the menu," says Chris Mason, a professor of regenerative medicine at University College London, who wasn't involved in the work.

To turn induced pluripotent stem (iPS) cells into a specific tissue type, they are typically placed in a soup of DNA and signalling molecules. These enter the cells and flick certain epigenetic switches. What gets turned on or off depends on the ingredients in the soup. "The problem is that there are tens of thousands of these switches that all need to be set in the right way," says Mason. Another hurdle is that all cells in the soup are influenced in the same way and grow into the same tissue type. But a piece of liver tissue, say, is not the same as a functioning liver. The issue is even more apparent with complex organs such as hearts, says Guye.

Read the full article at Next Big Future