The mind
If the mind is "in" the brain and the structures of the brain including the instructions to modify the connection between different parts of the brain are encoded in our genetics either as a DNA sequence, a process guided by a combination of DNA sequences, or a combination of DNA sequence combinations and external biochemistry (the construction of the brain in the fetus must come from somewhere), then we may conclude that the instructions for building a self-conscious machine exists within the interactions of DNA and external biochemistry. Hence we can program a sufficiently powerful computer to implement these instructions to build a self-conscious machine.
John G.