Identification of transgene flanking sequences in a pre-market safety assessed sugarcane in Argentina

ENRIQUE, RAMÓN; KURT, DANIEL; IBARRA-LACLETTE, ENRIQUE; NOGUERA, ALDO; WELIN, BJORN; CASTAGNARO, ATILIO

CROP BREEDING AND APPLIED BIOTECHNOLOGY

BRAZILIAN SOC PLANT BREEDING

Año: 2021 vol. 21

1518-7853

A prerequisite forcommercial release of a transgenic crop variety in Argentina and othercountries in the world is the identification and sequence analysis of thetransgene(s) insertion site in the plant genome. When analyzing aglyphosate-resistant transgenic sugarcane line TUC87-3RG, a high number oftransgene inserts was found by Southern blot analysis. By using an approach oftargeted sequence enrichment coupled with second-generation sequencing (SGS)and bioinformatic analyses we were able to identify and subsequently analyzeall flanking sequences to these transgene insertions in the sugarcane genome.Out of 29 candidate contigs, 18 were confirmed as junction sequences by meansof PCR reactions and did not match essential genes in published sugarcanegenomes. The outlined methodology represents an efficient strategy forcharacterization of flanking sequences corresponding to multiple inserts of atransgene in a large, complex and not fully sequenced plant genome such as theone of sugarcane.