GMO Myths and Truths

1. The genetic engineering technique
The World Health Organization defines genetically modified organisms (GMOs) as
“organisms in which the genetic material (DNA) has been altered in a way that does not
occur naturally”. 1 European legislation is more specific, defining GMOs as organisms in
which “the genetic material has been altered in a way that does not occur naturally by
mating and/or natural recombination”. 2
Typically genetic engineering involves manipulating an organism’s genetic material
(genome) in the laboratory by the insertion of one or more new pieces of DNA or by the
modification of one or more of the base unit letters of the genetic code. This re-programmes
the cells of the genetically modified organism to make a new protein or to modify the
structure and function of an existing protein. Genetic modification (GM) confers new
properties or “traits” that are not naturally present in the organism.
Among the manipulations included within GM are:
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Transferring of genes from related and/or totally unrelated organisms
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Modifying information in a gene (“gene editing”)
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Moving, deleting, or multiplying genes within a living organism
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Splicing together pieces of existing genes, or constructing new ones.
When incorporated into the DNA of an organism, genetically modified genes modify the
functional characteristics – the traits – of an organism. The most common traits in the GM
crops currently on the market are the expression of proteins designed to kill insects that
try to eat the crop or to make the crop tolerant to an herbicide. However, in theory, the new
proteins expressed in GM crops could have a wide range of functions.
What is DNA?
DNA stands for deoxyribonucleic acid. DNA molecules are found in the nucleus of every
cell. Within the DNA molecule are segments called genes, which can number in the tens of
thousands. Genes contain the instructions that guide the development and functioning of
all known living organisms and viruses.
The main role of DNA is the storage of biological information. Information stored within
genes is expressed as physical characteristics or traits, such as height, dark skin, red hair, or
blue eyes.
There are four subunits of the DNA molecule, called “bases”. These are the “letters” of the
genetic alphabet. Information is stored in DNA in the sequence of these letters, just as
information is stored on this page in the sequence of the letters of our 26-letter alphabet.
Each gene is a specific sequence of genetic letters and can be likened to a blueprint, recipe,
or code for a specific protein or set of proteins. The genome of an organism is the collection
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