Armies of super-soldiers were a step closer to reality today after China announced it was genetically engineering hyper-muscular super-dogs. The dogs, which are test tube bred in a lab, have twice the muscle mass of their natural counterparts and are considerably stronger and faster. The canine genome has been especially difficult to engineer and replicate – but its close similarity to the human genome means it has long been the prize of geneticists. Now the Chinese success has led to fears the same technology could be used to create weaponised super-humans – typifed in Marvel Comics by Captain America and his foes