QI inquired about genetic engineering of fodder crops and received this answer: "Molecular approaches to improvement of guinea grass, an important tropical and subtropical forage for cattle, have included genetic sequencing and marker-assisted breeding. To

I inquired about genetic engineering of fodder crops and received this answer: "Molecular approaches to improvement of guinea grass, an important tropical and subtropical forage for cattle, have included genetic sequencing and marker-assisted breeding. To our knowledge, genetic engineering has not yet been undertaken." Please define "genetic sequencing and marker-assisted breeding". How do these techniques differ from genetic engineering? Thanks

AExpert Answer

The genes that make up the blue print for an organism are carried on its DNA, which consists of a string with information coded much like letters and words. Genes or sets of genes determine many of the physical and biochemical characteristics of the organism – for example a gene for growth rate, or a set of genes that make a plant drought tolerant. Genetic sequencing is the determination of the precise DNA sequences that make up the genes of an organism (the Human Genome Project is the most famous example of this).  Using this information, researchers can identify certain DNA elements that are associated with particular plant characteristics of interest (“molecular markers”). Breeders can then use these markers to quickly identify individual plants that have the desired characteristics without having to actually grow the plants in the field.  Breeders choose individual plants for breeding that have the markers for the characteristics they need and quickly set aside the plants that do not. This is called “marker assisted selection” or “marker assisted breeding”. This technique allows breeders to cross-breed individual plants to efficiently and reliably add desired characteristics to particular crop varieties. By contrast, genetic engineering involves directly changing the DNA sequences to alter or add to the plants’ genes and create new characteristics.

Posted on February 2, 2018
Dr. Larry Gilbertson, PhD, Genomics Strategy Lead at Monsanto, explains how GMOs are “created” or made exactly, answering a lot of common questions about this process in this post. Watch as he prepares to create a GMO here.     Additionally, the below infographic details what a GMO is and the lifecycle it goes through to be developed.     Steve Savage, Consultant, Savage & Associates, explains what the future of GMOs may be like in this... Read More
Posted on February 2, 2018
A former response to a similar question answered by Dave Kovalic, Regulatory New Technology Lead at Monsanto, also provides information on scientific advancements and how they [Monsanto] affirm safety prior to targeted vector insertion.   “For context, it is important to recognize that random genome insertions have been naturally occurring in crops over the ~10,000-year history of agriculture.  In some crops, more than 90 percent of the genome consists of these... Read More
Posted on February 2, 2018
In terms of the science behind the technology to create GMOs, scientists have a much better understanding how a transgene is delivered and stably integrated into a chromosome (or genome). Many GMO products, such as Bt corn, were made using Agrobacterium cells to deliver useful trait genes into the plant cells. Scientists were able to dissect the different steps of this natural gene delivery system encoded by Agrobacterium. We now have a good understanding of the interactions between... Read More