FAQ: Why is the desired mutation missing from the transformants that I screened?

Although this is not a common result, there are a few known causes for background transformants: 1) excessive plasmid in the PCR, 2) selection against specific DNA structures such as inverted or tandem repeats, and 3) selection against the recombinant protein by the host E. coli cells.
  1. TroubleshootingTipsQ5SiteDirectedMutagenisis_720

    Troubleshooting tips for Q5® Site-Directed Mutagenesis Kit

    Tips for commonly encountered challenges in site-directed mutagenesis.