Mini-chromosomes

Where a transgene incorporates into a plant’s chromosomes can not be controlled. So, scientists have to transform many plants, and hope that at least one individual didn’t have the transgene interrupt a native gene. One solution to this problem is called a mini-chromosome. This technique uses the natural centromere sequence of an organism to build an entirely new chromosome that would be passed on to successive generations. The mini-chromosome can then be filled with a combination of genes, knowing that no native genes will be interrupted. Plants could be transformed with entire pathways, using this technology. The applications include improving field traits and nutrition, as well as things like making biofuels and bioplastics.
This research has been going on for a while, but the newest publishing shows that the mini-chromosome can be passed on to the next generation as a normal chromosome. From SD, Transgenics Transformed:

The maize mini-chromosome, once introduced, behaves much like an ordinary chromosome. It remains distinct from the other chromosomes. Its gene cassette is structurally stable from generation to generation. The genes it carries are expressed and it is transmitted through mitosis and meiosis.

The scientists started a company called Chromatin, which sold non-exclusive rights to Monsanto in May. Other companies are looking to get involved.
I’m really excited about this idea. One of the problems with genetic engineering is our inability to control where a gene inserts into the genome. Mini-chromosomes eliminate that problem and allow the scientist to add many genes instead of just one. It would be nice if they were still hiring when I am ready to graduate!

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