The research shows it is feasible to improve mental ability by tinkering with the genes involved with producing or interacting with the key neuro- transmitters of the brain - a step towards designer babies.
The study also paves the way to designing drugs that could improve learning and boost memory in people suffering from age-related disorders such as Alzheimer's and Parkinson's disease.
A team of scientists genetically engineered the genes of the mice to boost levels of a brain protein that acts as a receptor for a key neurotransmitter, called NMDA, which is known to be involved with memory and learning.
The genetically engineered mice performed significantly better than ordinary mice in a range of tests such as learning how to escape from a maze or how to locate a sunken platform in a water tank.
"This points to the possibility that enhancement of learning and memory or even IQ is feasible through genetic means, through genetic engineering," said Joe Tsien, assistant professor of molecular biology at Princeton University, who led the research team.
Professor Tsien nicknamed the smart mice Doogie, after the teenage genius in the American television show Doogie Howser, M.D.
Research published in the journal Nature showed that the enhanced learning and memory abilities of the smart mice were the result of an over-expression of a particular protein sub-unit of the NMDA receptors in the brain. Now that the precise role of this brain protein is known, drug companies can develop ways of interacting with it to reproduce the effect of enhancing cognitive ability, said Tim Bliss, head of neurophysiology at the National Institute for Medical Research at Mill Hill in London.
"We know that the same gene and protein are present in humans and it is likely that the same neural mechanisms are used in mice and men. So the research is likely to be useful in the design of drugs for memory disorders," Dr Bliss said.
"It would be a way of alleviating the problems of memory in an ageing population. We know that these animals are in some sense smarter and have better memories," he said.
A more controversial, and ethically questionable, application of the research would be to alter the genes of babies to overcome inherited disorders or to improve the chances of a better academic performance in later life.
"What we are looking at is the baby steps toward a world in which we can design our descendants," said Arthur Caplan, director of Pennsylvania Health System and a leading bioethicist. "I don't think that is necessarily bad. Finding ways to repair autism or mental retardation associated with Down's syndrome or Alzhei-mer's or other disabling neurological diseases is a very good thing," he said.
Because of the inherent risks, it makes more sense ethically to begin applying this discovery to treating diseases and disorders rather than trying to create smarter babies, Dr Caplan said.Reuse content