Cloning chip

A chip that will automatically create hundreds of cloned embryos at a time is being developed by a Californian biotech company, New Scientist has learned.

If it lives up to its promise, the chip should help make cloning cheap and easy enough for companies to mass-produce identical copies of the best milk or meat producing animals for farmers. It might even be used for cloning human embryos.

The chip automates the process of nuclear transfer, the key step in cloning. The nuclear transfer array developed at Aegen Biosciences, by Richard Kuo and Gregory Baxter, could handle hundreds or even thousands of eggs at once. Kuo says they can routinely denucleate 30 to 50 sea urchin eggs at a time. They plan to start testing cow eggs in the next few weeks.

The prototype is a thin silicon slice a few centimetres across etched with hundreds of tiny wells, one for each egg. The trick is to spin the chip in a centrifuge, forcing the eggs' dense nuclei through a small hole at the bottom of each well. About 90% of the eggs can be successfully denucleated this way, Kuo says.

Kuo and Baxter are now working on the next step, which is to fuse a donor cell with the denucleated egg.

Kuo admits there is much work still to be done on the chip, but he believes it's worth the effort. One could submit different batches of eggs to various treatments, to find out which conditions improve success rates in cloning, he says. Such studies could also help researchers identify the factors in eggs that reprogram the added nucleus.