Eleventh Doctor (Ganger)
The Doctor was a Ganger created from the Time Lord of the same name. When a bolt of solar energy struck the vat the Flesh was contained in, it was able to form a copy of the Doctor from a measure of his genetic material, gained when he touched the Flesh.
This Ganger was created by the Flesh without instruction from the human workforce; seemingly by the consiousness that the Doctor was able to sense in the substance. Without human instruction, it took the Flesh longer to generate the Doctor Ganger than it did a human Ganger.
When the humans and the Doctor fled from the other Gangers into the church, this Ganger confronted them and told them to trust him. (DW: The Rebel Flesh)
At first, the Ganger had some trouble adapting to the Doctor's DNA due to the residual traces of his previous incarnations present in his body, causing him to briefly act in the manner of his third and fourth incarnations. He eventually stabilised into a form and manner virtually identical to the Doctor's; the only way to distinguish them was their difference in shoes, as the original Doctor had changed his after the initial scan. The two Doctors subsequently swapped shoes while their companions were distracted in order to prove that Gangers and humans were no different from each other.
The Ganger Doctor subsequently sacrificed himself to stop Ganger Jennifer, setting the sonic screwdriver to a frequency that would cause the Flesh to collapse in full knowledge that this would destroy him too, so that the others would be encouraged to negotiate better conditions for the Gangers. (DW: The Almost People)