The GM 'super-athletes'

Genetically modified 'super-athletes' could be the sports stars of the future, experts warned today.

They spoke out as scientists revealed they have already created a rat with double the average muscle strength. Rats given a gene injection were also able to withstand vigorous exercise for longer periods of time and recover more quickly.

Scientists behind the experiment claimed it is 'inevitable' that athletes would in the future inject themselves with the muscle-enhancing gene to improve their performance.

Athletics organisations were quick to respond today. A spokesman for UK Sport, which oversees all sport in Britain, said: 'We must take the potential threat of gene doping very seriously. With the money and prestige associated with top-level sport there is always the possibility that unscrupulous individuals might try to use newly developed methods to cheat the drug-testing system.'

Authorities are already developing tests to spot muscle-enhancing genes.

'Gene doping has already been identified by the World Anti-Doping Agency as one of its top five areas for research, with the aim of developing a suitable detection method,' the spokesman said.

Experts believe the injections could let average athletes train harder and for longer, letting them compete with world beaters such as long-distance runner Paula Radcliffe, who holds three world records.