A genetically modified organism (GMO) is a plant, animal or microorganism whose genetic code has been altered, subtracted, or added (either from the same species or a different species) in order to give it characteristics that it does not have naturally.

The techniques used to produce GMO’s are generally known as genetic engineering, and the main process to create GMO’s is recombinant DNA. This technique uses DNA molecules from different sources, combines them into one molecule to create a new set of genes, and transfers the new set into an organism, giving it modified or novel genes. It’s obvious that this kind of alterations are quite new, but indeed mankind has been specially breeding or crossing species in order to achieve better results for hundreds of years. Genetic engineering enables scientists to do this much faster and with more detail.

Transgenic organisms, a subset of GMOs, are organisms which have inserted DNA that originated in different species. Some GMOs contain no DNA from other species and are therefore not transgenic but cisgenic.

Examples of GMOs are highly diverse, and include animals such as mice, fish, transgenic plants (like altered bananas mixed with genes of fish to grow quickly, bigger or with more vitamins), or various microbes, such as fungi and bacteria. The generation and use of GMOs has many reasons, chief among them are their use in research that addresses fundamental or applied questions in biology or medicine, for the production of pharmaceuticals and industrial enzymes, and for direct, and often controversial, applications aimed at improving human health (gene therapy) or agriculture (golden rice).

Here is a video of the battle between GMOs and organic food. It is not linked with an explanation of GMOs bus it is funny and we like it.


  • Advantages and disadvantages of GMOs:


  • Fewer pesticides are needed to be used due to insect pest resistant plants.
  • Decrease in costs of growing and farming, due to the reduced use of pesticides.
  • Higher crop yields.
  • Less deforestation needed to feed the worlds growing population.
  • Decrease in food prices due to lower costs and higher yield. As people in poor countries spend over half of their income on food alone, lower food prices mean an automatic reduction of poverty.
  • More nutritious products.
  • Strict and very complete standards that GMOs have to full achieve.
  • Creation of “super foods” due to better knowledge. Super foods are types of food that are cheap to produce, grow fast in large quantities, highly nutritious.
  • New products. For examples, scientist identified the gene responsible for caffeine in coffee beans; by excluding this gene, decaffeinated coffee beans can be grown naturally.
  • Reduction of sicknesses and illnesses, as GMO crops are more nutritious. Vitamins and minerals can be provided to children and to people, where they were inaccessible before.
  • Developments of new kinds of crops that can be grown at extreme climates, for example, dry or freezing environments (like deserts). For example, scientist developed a type of tomato that grows in salty soil.


  • Harm to other organisms. For example genes and their effect included in a crop may turn out to be poisonous to insects.
  • Cross-pollination with traditional, organic plants. Cross pollination can occur at quite large distances. New genes may also be included in the offspring of the traditional, organic crops miles away. This makes it difficult to distinguish which crop field is organic, and which is not, posing a problem to the proper labelling of non-GMO food products.
  • Spread of new, more resistant “superweeds” and “superpests”.
  • Major trading countries that obtain most of the benefit from the production and trade of genetically modified crops. This might cause more geopolitical conflicts.
  • Although it is not proved, GMOs may cause health problems.
  • Possible damages to the environment.
  • Variations in tests and safety standards around the world that led to uncontrollable crops.
  • Unforeseen risks and dangers due to the complexity of nature.
  • Allergies may become more intense, and also, new allergy types may develop.





Work by  David, Iratxe, Perseo, Rubén and Santi.