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DNA& GENETICALLY MODIFIED FOODS

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Deoxyribonucleic acid (DNA)

is a molecule that encodes the genetic instructions used in the development and functioning of all known living organisms

It was difficult to determine the sole inventor of the DNA molecule because the research was gathered over a number of years and in a number of different stages.

Dr James Watson who, along with Professor Francis Crick, Dr Rosalind Franklin (and Professor Maurice Wilkins), discovered the double helix structure of DNA. in 1953

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1856-1865 Gregor Mendel founds genetics.

1869 Johann Friedrich discovers a weak acidic substance in a human nuclei he calls nucleon. It is later called DNA.

1882 Walther Fleming discovers chromosomes.

1902-1903 Walter Stanborough Sutton uses grasshoppers to discover that chromosomes have genes.

1924 Chromosomes are shown to be made of protein and DNA.

Process of Invention

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…

1928 Franklin Griffith figures out that genetic information can be transferred from heat-killed bacteria to live ones.

1944 Oswald Avery figures out that Griffith’s substance was DNA.

1953 Francis Crick, James Watson and Rosalind Franklin discover the double helix structure of DNA.

1961 Francis Crick and Sidney Bremmer figure out that three bases are needed to code for an amino acid

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Noble Prize Winners

Francis Harry Maurice Hugh Frederick Wilkins Compton Crick James Dewey Watson

The Nobel Prize in Physiology and Medicine 1962 was awarded jointly to Francis Harry Compton Crick, James Dewey Watson and Maurice Hugh Frederick Wilkins "for their discoveries concerning the molecular structure of nucleic acids and its significance for information transfer in living material".

Many voices have argued that the Nobel Prize should also have been awarded to Rosalind Franklin, since her experimental data provided a very important piece of evidence leading to the solving of the DNA structure.

Rosalind Franklin died in 1958. As a rule only living people can be nominated for the Nobel Prize,so the 1962 Nobel Prizewas out of the question.

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Genetically Modified Foods

Today DNA has many uses in technology for example in Forensics and in History and Anthropology.

Genetically modified foods are foods derived from genetically modified organisms

Typically, genetically modified foods are transgenic plant products: soybean, corn, and cotton seed oil.

Genetically engineered plants are generated in a laboratory by altering their genetic makeup and are tested in the laboratory for desired qualities.

Supporters claim it will feed the world and promote better health and ecological welfare. While others believe the food contains risks to human health.

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Advantages

• Crops are more productive and have a larger yield.

• Offer more nutritional value and better flavour.

• A possibility that they could eliminate allergy-causing properties in some foods.

• Inbuilt resistance to pests, weeds and disease.

• More capable of thriving in regions with poor soil or adverse climates.

• More environment friendly as they require less herbicides and pesticides.

• Foods are more resistant and stay ripe for longer so they can be shipped long distances or kept on shop shelves for longer periods.

• As more GMF crops can be grown on relatively small parcels of land, they are an answer to feeding growing world populations.

• Corporations insist that:

• Genetically modified foods are safe. Changing a few genes here and there does not make a crop toxic or dangerous.

• Why shouldn't we alter nature to meet our needs? There are many natural organisms that human beings have transformed to serve their purpose.

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Dangers of GMF’s

• Scientists can choose which genes to manipulate, but they don't yet know where in the DNA to precisely insert these genes and they have no way of controlling gene expression. Genes don't work in isolation, changing a few could change everything, with unpredictable results.

• The use of genetically modified food should not be encouraged without research into the risks.

• Not labelling these products is wrong and unfair to the consumers who should have the right to know what they are buying so they can decide for themselves whether they want to buy the food or not. Even if health safety factors are not an issue, some people might have moral or religious objections. They should not have to eat GMFs if they don't want to.

• Genetically modified crops pose a risk to food diversity as the plants are much more dominant.

• Herbicide-resistant and pesticide-resistant crops could give rise to super-weeds and super-pests that would need newer, stronger chemicals to destroy them.

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…

• GM crops cross-pollinate with nearby non-GM plants and could create ecological problems. If this were to happen with GM foods containing vaccines, antibiotics, contraceptives and so on, it would very well turn into a human health nightmare.

• The claim of ending world hunger with GMFs is false. World hunger is not caused by a shortage of food production, but by sheer mismanagement, and lack of access to food brought about by various social, financial and political causes.

• The new technology also interferes with traditional agricultural methods which may be more suited to local environments.

• GMFs are not the answer to world hunger and health. Instead we should focus on improving organic agricultural practices which are kinder to the earth and healthier for humans.

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Now, make your best choice!