Genetic Modification


12 déc. 2012 (il y a 8 années et 7 mois)

320 vue(s)

Genetic Modification:

As scientific understanding of DNA increases, so does the ability to copy
and alter the molecule. This is called genetic engineering or genetic
modification. The definition of genetic modification is 'any alteration of
genetic material (DNA or RNA) of an o
rganism by means that could not
occur naturally through mating or recombination'.

The genetic techniques involved could include:

transferring genes from one organism to

moving, deleting, modifying, or multiplying
genes within a living organism

modifying existing genes or constructing new
ones, and incorporating them into a new

There are many applications for genetic modification. For example,
human insulin for diabetics was previously obtained from genetically
engineered bacteria from

pigs. This represented a huge advance for
diabetic patients. The insulin produced by this process is not recognised
by the immune system, so problems suffered by diabetic patients in the
past involving development of antibodies and allergy to pig insulin
problem in the 1980s) are now totally absent. A variety of other enzymes
and chemicals are now also produced by genetically
modified bacteria.

Scientists are using genetic engineering in animals to produce improved
vaccines for animal diseases, and med
ical compounds for humans. The
term 'pharming' has been used to describe these concepts.

ally Modified Food:

is most commonly used to refer to crop plants created for human or animal
consumption using the latest molecular biology techniques. Thes
e plants have
been modified in the laboratory to enhance desired traits such as increased
resistance to herbicides or improved nutritional content.


Artificial Sweeteners

Chemicals on food: Boron on turnip,


tomatoes and cantalopes

that have modified ripening characteristics, soybeans
and sugarbeets that are resistant to herbicides (prevent weeds)

Strawberries, pineapples, sweet peppers
, tomatoes
and bananas have
all been genetically modified by scientists to remain fresh for longer


Human health risks


Unknown effects on human health

Video link:

, the first genetically modified animal to be sold as a

May 2002

Can strawberry crops be genetically engineered to survive frost? Photo by Ken Hammond.

Food can be engineered to prevent disease.

Rice with built
in Vitamin A that can help prevent blindness in
100 million children suffering from Vitamin A deficiency;

A to
mato that softens more slowly, allowing it to develop
longer on the vine and keep longer on the shelf;

Potatoes that absorb less fat when fried, changing the ever
popular french fries from junk food into a more nutritional

Strawberry crops that can s
urvive frost;

An apple with a vaccine against a virus that causes childhood

These are some of the benefits promised by biotechnology. The
debate over its benefits and safety, however, continues. Do we
really need to fear mutant weeds, killer tom
atoes, and giant
corn and will the benefits be delivered?