In Fig. 8 of the study, we suggested a strategy for targeted transgene transfer and, at the same time, removal of antibiotic marker genes. Unfortunately, a small mistake has been slipped in under (B) of this figure in “2. Recombination = induction of cre = removal of bar/hyg/cre” (Fladung & Becker 2010). The FRT site (stumped blue arrow) located at the 3′-end of the ‘gene-of-interest’ in the starting cassette has moved to the 5′-end of the ‘gene-of-interest’ in the next drawing. The correct position of the FRT site, however, is still at the 3′-end of the ‘gene-of-interest’ as shown in the corrected Fig. 8.
The consequence of the mistake is that a putative third recombination by external applied FLP as mentioned in the text would NOT remove the additional FRT/Lox-fragment but rather would lead to the removal of the ‘gene-of-interest’. Therefore, no third recombination is recommended.
Corrected Figure 8: