Meet Hobbie-J, the smartest rat in the world

A rat is impressing American scientists with her extraordinary intellect.

Hobbie-J has been dubbed the smartest rat in the world after its NR2B gene, which controls memory, was boosted as an embryo. The rodent can remember objects three times as long as its smartest peers and can better solve complicated puzzles like mazes.

The success of Hobbie-J, which is named after a Chinese cartoon character, brings new hope for future dementia patients, as it is thought the gene enhancement could one day be incorporated into a drug treatment for human brain disorders.

Dr Joe Z Tsien, who led the experiment at the Medical College of Georgia, said: “Hobbie-J can remember information for longer. It’s the equivalent of me giving you a telephone number and somehow you remembering it for an hour.

“Our study provides a solid basis for the rationale that the NR2B gene is critical to enhancing memory. That gene could be used for memory-enhancing drugs.”

Hobbie-J was injected with genetic material which meant the NR2B gene, which helps control the rate at which brain cells communicate, was more powerful. Its cells can communicate a little longer than other rats, boosting its memory.

Tsien undertook a similar experiment on a mouse named Doogie 10 years ago, but this trial shows memory enhancement can work on different types of mammal – paving the way for human use.

Although it could take decades to develop a safe drug, dementia organisations in the UK said the study was an exciting development. Andrew Scheuber from the Alzheimer’s Research Trust said: “This fascinating research involving rats may lead to new ways to reduce the risk of developing diseases like Alzheimer’s or to ameliorate dementia symptoms.

He added: “A treatment involving NR2B may have the potential to slow the deterioration that takes place in dementia patients, but it is too soon to tell.”

However, Dr John Hardy, professor of neuroscience at University College London, said the research would not help Alzheimer’s patients because they suffered from dying brain cells, not ineffective ones.

He also warned of a nightmare scenario whereby healthy humans would be given treatment, saying too much memory could fill up the human “hard drive”.

“It's very important for humans to be able to forget things,” he said. “That's simply so you don't fill up your brain with useless memories, and this is going to disturb that. You wouldn't be able to process new things properly.”

Developing a drug treatment is likely to be the only viable way of using gene enhancement, as genetically modifying human embryos is still highly controversial. But even a process like this would worry some activists.

Dr David King, Director of Human Genetics Alert said: “These data show vital it is for our society to control technologies of enhancement. Do we want to live in a world in which the rich can give themselves and their children even more advantages over the rest of us?”

Dr Sophie Petit-Zeman, from the Association of Medical Research Charities, agreed the concept should be treated with caution. “It is vital to stress the care which needs to be taken when moving this work from animals into man,” she said.

“There will be many steps before it can reach the clinic, and, rightly, many discussions about where the line should be drawn between seeking treatments for distressing illnesses and the potential to enhance memory in healthy people.”