The homology arms of the donor plasmid used in generating the TI{T-GEM}α-SpecCR00273-TG4.2 insertion were designed such that there is a small gap between the 3' end of the 5' arm and the 5' end of the 3' arm, thus the insertion is predicted to be accompanied by a deletion of 24bp of genomic sequence flanking the insertion site. The PCR check of the insertion gave a shorter than expected band for the right flank and the expected sized product for the left flank.