The U.S. Food and Drug Administration (FDA) has ruled that the new genetically modified strains of food do not need special labeling (thus many are unknowingly eating genetically modified foods). The FDA currently requires no labeling because it believes that genetically modified foods are not significantly different than hybrids developed by cross breeding.
Genetically modified foods are different, however, from hybrids. Whereas many hybrids are the results of crossing two or more varieties of the same species, genetically modified foods do not need to be. Actually, it is believed to be possible to insert the gene of an animal (or a different species of plant) into a plant in order to make a genetically modified plant, such cannot occur with normal hybrids: "Potatoes may be spliced with chicken genes, tomatoes spliced with fish genes, corn spliced with 'virus' genes, pigs spliced with human genes. Bacteria, insect, and animal combinations and various plant combinations produced. Manufacturers can sell bioengineered foods without [adequate] safety testing or disclosure.
Thursday, July 12, 2007
Tuesday, July 10, 2007
Controversies
Controversies
Safety
-Potential human health impact: allergens, transfer of antibiotic resistance markers, unknown effects
-Potential environmental impact: unintended transfer of transgenes through cross-pollination, unknown effects on other organisms (e.g., soil microbes), and loss of flora and fauna biodiversity
Access and Intellectual Property
-Domination of world food production by a few companies
Increasing dependence on Industralized nations by developing countries
Biopiracy—foreign exploitation of natural resources
Ethics
-Violation of natural organisms' intrinsic values
Tampering with nature by mixing genes among species
Objections to consuming animal genes in plants and vice versa
Stress for animal
Labeling
-Not mandatory in some countries (e.g., United States)
Mixing GM crops with non-GM confounds labeling attempts
Society
-New advances may be skewed to interests of rich countries
http://www.ornl.gov/sci/techresources/Human_Genome/elsi/gmfood.shtml
Safety
-Potential human health impact: allergens, transfer of antibiotic resistance markers, unknown effects
-Potential environmental impact: unintended transfer of transgenes through cross-pollination, unknown effects on other organisms (e.g., soil microbes), and loss of flora and fauna biodiversity
Access and Intellectual Property
-Domination of world food production by a few companies
Increasing dependence on Industralized nations by developing countries
Biopiracy—foreign exploitation of natural resources
Ethics
-Violation of natural organisms' intrinsic values
Tampering with nature by mixing genes among species
Objections to consuming animal genes in plants and vice versa
Stress for animal
Labeling
-Not mandatory in some countries (e.g., United States)
Mixing GM crops with non-GM confounds labeling attempts
Society
-New advances may be skewed to interests of rich countries
http://www.ornl.gov/sci/techresources/Human_Genome/elsi/gmfood.shtml
Friday, July 6, 2007
GM food benefits???
Benefits
Crops
-Enhanced taste and quality
-Reduced maturation time
-Increased nutrients, yields, and stress tolerance
-Improved resistance to disease, pests, and herbicides
-New products and growing techniques
Animals
-Increased resistance, productivity, hardiness, and feed efficiency
-Better yields of meat, eggs, and milk
-Improved animal health and diagnostic methods
Environment
"-Friendly" bioherbicides and bioinsecticides
-Conservation of soil, water, and energy
-Bioprocessing for forestry products
-Better natural waste management
-More efficient processing
Society
-Increased food security for growing populations
http://www.ornl.gov/sci/techresources/Human_Genome/elsi/gmfood.shtml
Tuesday, July 3, 2007
PCR
The analytical methods contain the following steps:
1.- Extraction of DNA:
It is necessary to extract the genetic material free from other impurities which might interfere in further steps of the analysis.
2.-PCR reaction ( Polymerase Chain Reaction)
The PCR reactions are suited to multiply and amplify specific fragments of DNA that are alien genes to the food being analysed.
The primer starter molecules used in the beginning of the reaction decides which sequence of DNA will be multiplied.
To avoid false negative results due to inhibit action of impurities during extraction of the DNA it is important to include a positive reaction.
3.-Making the PCR product visible Through gelelectrophoresis (agarosegelelectrophoresis).
The products of the PCR reaction can be made visible together with the determination of the length of the base pair, the alien gen.
4.-Confirmation of the results
The confirmation of the results are being made by controlling the sequence of the base in the PCR product using specific sequence restriction, hybridization with specific sonde Nested PCR and Sequencing The basic PCR gives only qualitative indications.
To obtain quantitative results the Competitive PCR or the RT-PCR should be used
1.- Extraction of DNA:
It is necessary to extract the genetic material free from other impurities which might interfere in further steps of the analysis.
2.-PCR reaction ( Polymerase Chain Reaction)
The PCR reactions are suited to multiply and amplify specific fragments of DNA that are alien genes to the food being analysed.
The primer starter molecules used in the beginning of the reaction decides which sequence of DNA will be multiplied.
To avoid false negative results due to inhibit action of impurities during extraction of the DNA it is important to include a positive reaction.
3.-Making the PCR product visible Through gelelectrophoresis (agarosegelelectrophoresis).
The products of the PCR reaction can be made visible together with the determination of the length of the base pair, the alien gen.
4.-Confirmation of the results
The confirmation of the results are being made by controlling the sequence of the base in the PCR product using specific sequence restriction, hybridization with specific sonde Nested PCR and Sequencing The basic PCR gives only qualitative indications.
To obtain quantitative results the Competitive PCR or the RT-PCR should be used
Sunday, July 1, 2007
Dna detection method
Western Blot
The method of Western Blot the extraction of the transgenetic protein from the food is done by means of a nitro-cellulose membrane which binds the proteins. The membrane is immersed in a solution of a specific antibody together with an enzyme resulting in a colour reaction. This method is very labour intensive and therefore not being used in routine.
The method of Western Blot the extraction of the transgenetic protein from the food is done by means of a nitro-cellulose membrane which binds the proteins. The membrane is immersed in a solution of a specific antibody together with an enzyme resulting in a colour reaction. This method is very labour intensive and therefore not being used in routine.
Thursday, June 28, 2007
DNA probes
What are DNA Probes?
Little more than a decade ago, toxic phytoplankton monitoring with DNA probes was still in the realm of science fiction. Today it is a reality. Probes for some key micro-algae are already in commercial use and ultimately DNA probes could become a major HAB monitoring tool.
What exactly are they?
DNA probes have been in use for more than a decade in medicine and dentistry, but they have only recently been developed with the aquaculture industry in mind. The DNA of a selected micro-alga is sequenced, and the sequence of nucleotides that makes up its genetic code is compared with that of other related algae using readily available computer software packages. Unique nucleotide "signatures" (usually between 15 and 50 nucleotides) are selected to develop into probes. The ribosomal RNA (rRNA) of the cell is targeted because it is abundant in cells and so good recognition, or a good "hit", is ensured. The probes will have some "tag", for example fluorescein, attached for easy recognition of a positive assay. The probes can be prepared for a number of different assay systems, but require intensive trialling to ensure there is no cross-reactivity with other micro-algae species.
Pseudo-nitzschia and Alexandrium whole cell format DNA probes are now used routinely in New Zealand's phytoplankton monitoring programmes as an aid to risk management decision-making, and the monitoring laboratory (Cawthron Institute) is approved by International Accreditation New Zealand (recognised under ISO17025).
How are they used?
Identification of micro-algae to species level is vital so that shellfish growers, and health and industry officials, can make safe and economically sound harvesting decisions.
Standard phytoplankton monitoring methods involve identifying toxic species in a water sample and counting them. It is labour intensive and requires expert training in the recognition of the critical algae. In some case scanning electron microscope preparation of samples can be required to differentiate species. This can be expensive and cause delays. DNA probes offer an exciting and rapid alternative
http://www.geneprobes.org/whatare.htm
Little more than a decade ago, toxic phytoplankton monitoring with DNA probes was still in the realm of science fiction. Today it is a reality. Probes for some key micro-algae are already in commercial use and ultimately DNA probes could become a major HAB monitoring tool.
What exactly are they?
DNA probes have been in use for more than a decade in medicine and dentistry, but they have only recently been developed with the aquaculture industry in mind. The DNA of a selected micro-alga is sequenced, and the sequence of nucleotides that makes up its genetic code is compared with that of other related algae using readily available computer software packages. Unique nucleotide "signatures" (usually between 15 and 50 nucleotides) are selected to develop into probes. The ribosomal RNA (rRNA) of the cell is targeted because it is abundant in cells and so good recognition, or a good "hit", is ensured. The probes will have some "tag", for example fluorescein, attached for easy recognition of a positive assay. The probes can be prepared for a number of different assay systems, but require intensive trialling to ensure there is no cross-reactivity with other micro-algae species.
Pseudo-nitzschia and Alexandrium whole cell format DNA probes are now used routinely in New Zealand's phytoplankton monitoring programmes as an aid to risk management decision-making, and the monitoring laboratory (Cawthron Institute) is approved by International Accreditation New Zealand (recognised under ISO17025).
How are they used?
Identification of micro-algae to species level is vital so that shellfish growers, and health and industry officials, can make safe and economically sound harvesting decisions.
Standard phytoplankton monitoring methods involve identifying toxic species in a water sample and counting them. It is labour intensive and requires expert training in the recognition of the critical algae. In some case scanning electron microscope preparation of samples can be required to differentiate species. This can be expensive and cause delays. DNA probes offer an exciting and rapid alternative
http://www.geneprobes.org/whatare.htm
Saturday, June 23, 2007
Know more about genetic modified food...
What are Genetically Modified (GM) Foods?
GM is a special set of technologies that alter the genetic makeup of such living organisms as animals, plants, or bacteria. Biotechnology, a more general term, refers to using living organisms or their components, such as enzymes, to make products that include wine, cheese, beer, and yogurt.
Combining genes from different organisms is known as recombinant DNA technology, and the resulting organism is said to be "genetically modified," "genetically engineered," or "transgenic." GM products (current or in the pipeline) include medicines and vaccines, foods and food ingredients, feeds, and fibers.
Locating genes for important traits—such as those conferring insect resistance or desired nutrients—is one of the most limiting steps in the process. However, genome sequencing and discovery programs for hundreds of different organisms are generating detailed maps along with data-analyzing technologies to understand and use them.
History.....
In 2003, about 167 million acres (67.7 million hectares) grown by 7 million farmers in 18 countries were planted with transgenic crops, the principal ones being herbicide- and insecticide-resistant soybeans, corn, cotton, and canola. Other crops grown commercially or field-tested are a sweet potato resistant to a virus that could decimate most of the African harvest, rice with increased iron and vitamins that may alleviate chronic malnutrition in Asian countries, and a variety of plants able to survive weather extremes.
On the horizon are bananas that produce human vaccines against infectious diseases such as hepatitis B; fish that mature more quickly; fruit and nut trees that yield years earlier, and plants that produce new plastics with unique properties.
In 2003, countries that grew 99% of the global transgenic crops were the United States (63%), Argentina (21%), Canada (6%), Brazil (4%), and China (4%), and South Africa (1%). Although growth is expected to plateau in industrialized countries, it is increasing in developing countries. The next decade will see exponential progress in GM product development as researchers gain increasing and unprecedented access to genomic resources that are applicable to organisms beyond the scope of individual projects.
GM food....effects......
Technologies for genetically modifying (GM) foods offer dramatic promise for meeting some areas of greatest challenge for the 21st century. Like all new technologies, they also poses some risks, both known and unknown. Controversies surrounding GM foods and crops commonly focus on human and environmental safety, labeling and consumer choice, intellectual property rights, ethics, food security, poverty reduction, and environmental conservation
GM is a special set of technologies that alter the genetic makeup of such living organisms as animals, plants, or bacteria. Biotechnology, a more general term, refers to using living organisms or their components, such as enzymes, to make products that include wine, cheese, beer, and yogurt.
Combining genes from different organisms is known as recombinant DNA technology, and the resulting organism is said to be "genetically modified," "genetically engineered," or "transgenic." GM products (current or in the pipeline) include medicines and vaccines, foods and food ingredients, feeds, and fibers.
Locating genes for important traits—such as those conferring insect resistance or desired nutrients—is one of the most limiting steps in the process. However, genome sequencing and discovery programs for hundreds of different organisms are generating detailed maps along with data-analyzing technologies to understand and use them.
History.....
In 2003, about 167 million acres (67.7 million hectares) grown by 7 million farmers in 18 countries were planted with transgenic crops, the principal ones being herbicide- and insecticide-resistant soybeans, corn, cotton, and canola. Other crops grown commercially or field-tested are a sweet potato resistant to a virus that could decimate most of the African harvest, rice with increased iron and vitamins that may alleviate chronic malnutrition in Asian countries, and a variety of plants able to survive weather extremes.
On the horizon are bananas that produce human vaccines against infectious diseases such as hepatitis B; fish that mature more quickly; fruit and nut trees that yield years earlier, and plants that produce new plastics with unique properties.
In 2003, countries that grew 99% of the global transgenic crops were the United States (63%), Argentina (21%), Canada (6%), Brazil (4%), and China (4%), and South Africa (1%). Although growth is expected to plateau in industrialized countries, it is increasing in developing countries. The next decade will see exponential progress in GM product development as researchers gain increasing and unprecedented access to genomic resources that are applicable to organisms beyond the scope of individual projects.
GM food....effects......
Technologies for genetically modifying (GM) foods offer dramatic promise for meeting some areas of greatest challenge for the 21st century. Like all new technologies, they also poses some risks, both known and unknown. Controversies surrounding GM foods and crops commonly focus on human and environmental safety, labeling and consumer choice, intellectual property rights, ethics, food security, poverty reduction, and environmental conservation
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