What’s in my lunch? Analyzing GM foods in your classroom laboratory.

I always like to teach biotechnology in the context of its real-world uses.  For example, one “hot-button” issue relates to the genetic modification of plants and animals in agriculture.  Newspapers, popular magazines, and even our Facebook feeds are full of statements about genetically modified organisms that may or may not be true.

Below are some commonly asked questions about genetically modified organisms to help you get started with learning more about this topic.

What are genetically modified organisms?

A genetically modified organism, or GMO, is any plant, animal or microorganism whose DNA sequence has been changed using traditional or genetic engineering techniques.

What is the future of GMOs?

Appearance of white rice (L) versus Golden rice (L).  The golden color comes from beta-carotine.  © IRRI
Appearance of white rice (L) versus Golden rice (L). The golden color comes from beta-carotine. © IRRI

Current plant biotechnology promises to increase both the yield and nutritional value of many food crops.  One success story is that of “golden rice”.  Normally, rice, a staple food for much of the world population, does not provide β-carotene or vitamin A.  Because vitamin A deficiency is a widespread problem in developing countries, rice has been modified to produce β-carotene, a precursor of vitamin A. Cultivation of “golden rice” and other nutrient-supplemented crops in these areas represents major progress in combating malnutrition.  In addition to boosting crop yields and enhancing nutrition, transgenic technology could be used to create allergy-free peanuts and low protein rice for people with kidney disease.

How do we make GMOs?

Humans have long genetically modified plants and animals using traditional husbandry techniques like selective breeding and conventional hybridization.  These techniques have been used to increase crops’ yields, domesticate animals, and to cultivate microbes that ferment our foods.  Today, genetic engineering allows scientists to directly manipulate DNA

PCR Amplification of DNA sequences used in GM organisms.  ©Edvotek 2014
PCR Amplification of DNA sequences used in GM organisms. ©Edvotek 2014

sequences to generate desirable characteristics.  These engineered genes, called transgenes, can be inserted, deleted or mutated in a matter of weeks using recombinant DNA technology.

Many technologies have been developed to create transgenic plants.    One example is the biolistic (or “gene gun”) method.  Using this approach, the transgene DNA is shot through the walls of plant cells, where it is incorporated into the host’s genome.  Another method relies on A. tumifacens, a natural plant parasite.  Genetic engineers use recombinant DNA technology to replace a bacterial gene with a gene of interest.  The bacteria transfer the transgene to the host, thus creating a transgenic plant.

How are GM foods regulated?

The responsibility of public health and policy concerning GMOs rests on the shoulders of the government and the biotechnology industry.  The United States government has carefully monitored GM food production and created strict regulations to protect the health of Americans.  To gain acceptance, the plant biotechnology industry must communicate its research and development of new GM food products effectively to these agencies.

Interested in using this topic in your classroom?

When teaching about GM organisms, I like to have the students research the benefits and the drawback of the technology.  This is a great way to teach your students critical thinking and reading skills.  Make sure to review your students source materials, as there is a lot of misinformation on the internet.

Depending on the level of your students, there are several different experiments that can be used to teach this lesson.  One that I like is our Kit 962, Identification of Genetically Modified Foods Using PCR.  Students can test foods from the supermarket for the presence of common genetic modifications.  If you don’t have a thermal cycler, check out kit 121 for a ready-to-load simulation.

We also have presented this material in many of our Professional Development courses.  Check out our PowerPoint Presentation for our take on the topic, and some inspiration for your lessons.  Happy teaching!