There are currently three main ways to insert genetic information into a higher plant: CRISPR-Cas9, using Agrobacterium tumefaciens, and a Gene Gun.
We will focus on the Gene Gun for this article. The problem with a Gene Gun is the expression. Randomly inserting a gene into an organism causes the expression to decline after time even after screening and selection.
We have gotten better at using the Gene Gun by also incorporating regulatory genes with the gene of interest, however, the placement of that gene is uncontrolled and would effect expression.
What is the solution? Insert a whole chromosome. Let’s say you want to insert a defense protein from Ampelocera hottlei into Ulmus americana, American Elm as a solution for Disease.
After DNA extraction restriction enzyme would be used to cut the DNA selectively. A marker would be used to identify the target gene. Electrophoresis would then separate the large piece of DNA with the target gene. This piece would then go through PCR amplification. The DNA then would be coated onto a gold particle and shot into the target organism, American Elm.
Assuming that the gene gun insertion process would allow this large piece of DNA the benefits of doing this would be that most regulatory genes would also go with the target gene and expression would be preserved. In addition, other genes may carry other unknown benefits to the target organism.