Nanogene Nanogenes were a type of sub - atomic robot capable of healing wounds and restoring lost appendages . They could also act as a defence mechanism , creating soldiers capable of protecting or guarding planets and technology . Abilities . Nanogenes looked like minuscule , glowing specks that buzzed around their targets . They were capable of healing superficial wounds in seconds and even reanimating the dead , provided they had an existing template for the individual . They were used as medical equipment by certain advanced races such as the Chula . If a patient had lost body parts such as a limb , the nanogenes could regrow a new one from scratch . However , upon identifying the first member of an uncatalogued species nanogenes could confuse their biology as part of the overall template , including wounds and body equipment , and then reconfigure that person ' s body in a misshapen form and any others who came in contact with the nanogenes . In this respect , nanogenes were capable of being guided or outright reprogrammed to identify their mistakes and assume a correct template . Nanongenes could also be deactivated altogether to prevent accidental transformations and misuse of the nanogenes , as well as hide their presence on worlds where the technology was introduced before its time . The Chula used nanogenes in war . These nanogenes enhanced the subject ' s physical abilities , giving them superhuman strength , telepathic abilities and Om - Com capabilities . They also could reside within a human host such as the Empty Child , and would emerge visibly when something of interest was revealed , such as when they encountered Jamie ' s mother Nancy and realised their error after scanning her ; they recognised her as Jamie ' s mother and corrected the alterations they had performed on him . ( TV : " The Empty Child " / " The Doctor Dances " ) History . In 1941 , the con man Captain Jack Harkness crashed a Chula ambulance in London , planning to sell it and then allow it to be destroyed by bombing . At some time the ship was damaged and millions of nanogenes released . This led to the Empty Child plague when the nanogenes found a dead child , wearing a gas mask and with fatal wounds . As they had never encountered a human before , they believed that this was their default form . With the child as a template , they set about transforming all humans to match his attributes , with injuries and a gas mask bonded to the face . They eventually recognised the real DNA by finding the child ' s mother , therefore coming to the conclusion that they were incorrect , and reversed the process . In addition to this , they also restored the missing leg of Mrs Harcourt and healed a minor burn the Ninth Doctor suffered on the palm of his hand . ( TV : " The Empty Child " / " The Doctor Dances " ) Rose Tyler noted nanogenes among the things she had seen when she was sceptical that the newly regenerated Tenth Doctor was the man she knew . ( TV : " Children in Need Special " ) Nanogenes were apparently still in use by the year 5 billion , as the Tenth Doctor " borrowed " some from the New New York Hospital . ( PROSE : " Peacemaker " ) The Eleventh Doctor referred to the Dalek nanocloud as nanogenes . The Daleks used this nanocloud to convert human s into Dalek puppet s . ( TV : " Asylum of the Daleks " )