Monday, December 8, 2014

Creating mice with half-human brains

Mice have been created whose brains are half human. As a result, the animals are smarter than their siblings. ...

The altered mice still have mouse neurons – the "thinking" cells that make up around half of all their brain cells. But practically all the glial cells in their brains, the ones that support the neurons, are human. ...

[Steve] Goldman's team extracted immature glial cells from donated human fetuses. They injected them into mouse pups where they developed into astrocytes, a star-shaped type of glial cell. ...

Astrocytes are vital for conscious thought, because they help to strengthen the connections between neurons, called synapses. ...

A battery of standard tests for mouse memory and cognition showed that the mice with human astrocytes are much smarter than their mousy peers. ...

To explore further how the human astrocytes affect intelligence, memory and learning, Goldman is already grafting the cells into rats, which are more intelligent than mice. ...

...Goldman is quick to dismiss any idea that the added cells somehow make the mice more human. ...

However, the team decided not to try putting human cells into monkeys. "We briefly considered it but decided not to because of all the potential ethical issues," Goldman says.
--Andy Coghlan, New Scientist, on real-life rats of NIMH and Algernons. HT: Marginal Revolution