Circular DNA molecule having a conditional origin of replication, process for their preparation and their use in gene therapy

摘要

Disclosed is a method for detecting a plasmid copy-up mutation, the method comprising: (a) introducing at least one mutation into a target sequence; (b) transforming the mutated target sequence into a host cell comprising a plasmid, wherein the plasmid comprises a nucleotide sequence encoding urolll methyltransferase and the copy number of the plasmid is effected by the target sequence; (c) growing the host cell under conditions wherein the nucleotide sequence is expressed to produce a culture of host cells; (d) exposing the culture of host cells to W light; and (e) detecting fluorescence produced by the culture of host cells.