Human Gemone Project• Begun formally in 1990 the international projects aims were:• identify all the approximate 30,000 genes in human DNA.• determine the sequences of the 3 billion chemical base pairs that make up human DNA.• store this information in database.• improve tools for data analysis.• transfer related technologies to the private sector.• address the ethical, legal, and social issues (ELSI) that may arise from the project.• To help achieve these goals, researchers also are studying the genetic makeup of several nonhuman organisms. These include the common human gut bacterium Escherichia coli, the fruit fly, and the laboratory mouse. Why?...
Because…• The genetic code is universal• All known organisms use the same genetic code.• Therefore in principle if we transfer a gene from one species to another it should still be transcribed and translated into the same protein
Gene Transfer Stage 1: obtaining the gene for transfer:• Restriction enzymes are used to cut out the useful gene that is to be transferred.• Note the sticky ends of unattached hydrogen bonds.
Stage 2: Preparing a vector for the transferred gene:• Plasmids are small circular DNA molecules found in bacteria.• These can be cut with the same restriction enzyme as above.• This leaves the same complementary sticky ends in the plasmid• The plasmid can be cut at particular sites. These are called restriction sites and some are named in the diagram.
Stage3: Recombinant DNA
Stage 4: Isolation of transformed cells• Recombinant DNA is introduced into the host cells• Many cells remain untransformed• Some cells are transformed to contain the recombinant DNA.• These transformed cells must be separated from untransformed• Add ‘extra’ genes to help separate
GMO• Genetically modified organism (GMO) is an organism containing a transplanted gene.• Vitamin production, herbicide resistance, or…
The benefits of GMO include:• Increased yields particularly in regions of food shortage.• Yields of crops with specific dietary requirement such as vitamins and minerals.• Crops that do not spoil so easily during storage.• GM animals produce similar effect including higher meat yields.
Disadvantages• The concerns about GMO usually revolve around:• The foods (animal and plant) may be considered un-natural and unsafe for human consumption.• There is a risk of the escape of genes into the environment where they may be passed to other organisms with unknown effects.