Distribution of Transgenes in Wheat Co-transformed through Particle Bombardment

Scientist Yonghua Han from Jiangsu Normal University and colleagues conducted a study to identify the distribution of transgene loci in 45 transgenic wheat lines with co-transformed high molecular weight glutenin subunit genes and the selectable marker bar using fluorescence in situ hybridization.

The researchers observed that the transgene loci distribute randomly throughout the genome and integrate into various locations along individual chromosomes. There was minimal tendency for transgenes to be localized in distal chromosome regions. High proportions of transgenes in separate plasmids integrated at the same site and only 7 lines had 2 or 3 loci. These loci have the tendency not to segregate frequently in subsequent generations thus, it is hard to eliminate selectable markers from transgenic lines after regeneration. Furthermore, three transgenic lines were found to be linked with rearranged chromosomes, which may imply a close relationship between particle bombardment-mediated transgene integration and chromosomal rearrangements.

Read the abstract in Transgenic Research.