CloningCloning

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IX Gene TransferIX Gene Transfer

Some peopleSome people’’s blood does not clot due to lack of protein s blood does not clot due to lack of protein IXIX

If they can be supplied If they can be supplied problem solvedproblem solved

Production of factor IX is cheapest in a transgenic sheepProduction of factor IX is cheapest in a transgenic sheep

This is done by associating the human This is done by associating the human gene which codes gene which codes for the production of IXfor the production of IX with with the genetic information for the genetic information for milk production in sheep. milk production in sheep.

Basically:

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• A ewe is treated with fertility drugs to create super-ovulation. Eggs are inseminated.

• Each fertilized egg has the transgene injected.

• A surrogate ewe has the egg implanted for gestation.

• Lambs are born which are transgenic, GMO for this factor IX gene.

• Each Lamb when mature can produce milk.

• The factor IX protein is in the milk and so must be isolated and purified before use in human.

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• Gene that codes for protein IX can be inserted in plasmid of Gene that codes for protein IX can be inserted in plasmid of host cell (sheep) and plasmid can be inserted in sheep, where host cell (sheep) and plasmid can be inserted in sheep, where protein will be producedprotein will be produced

• Sheep can synthesize factor IXSheep can synthesize factor IX

• The messenger RNA which codes for factor IX is extracted from The messenger RNA which codes for factor IX is extracted from a human pancreatic cell which produces factor IX. a human pancreatic cell which produces factor IX.

• A selected plasmid is cut using restriction enzymes A selected plasmid is cut using restriction enzymes ((endonucleaseendonuclease) which cut the DNA at specific base sequences ) which cut the DNA at specific base sequences from the host cell (sheep).from the host cell (sheep).

• The plasmid from host cell and isolated gene from donor cell The plasmid from host cell and isolated gene from donor cell are “stuck” together by enzyme are “stuck” together by enzyme DNADNA ligaseligase. Plasmid is now . Plasmid is now recombinant recombinant and is used as a tool to introduce a new gene in and is used as a tool to introduce a new gene in an organism.an organism.

• Recombinant plasmid is inserted in sheep Recombinant plasmid is inserted in sheep sheep produces sheep produces factor IX found in milkfactor IX found in milk. .

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How it is doneHow it is done

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Advantages / DisadvantagesAdvantages / Disadvantages

Advantages Disadvantages

Cheapest way to produce factor XIIncidence rate is 1 / 100 000. Therefore is it right to genetically modify sheep for such a

small sample of population?

Production of transgenic sheep by nuclear transfer requires fewer than half the animals

needed for pronuclear microinjectionPotential danger to sheep

Salt tolerance in tomato Salt tolerance in tomato plantsplants

The new salt-proof tomato isolates salt The new salt-proof tomato isolates salt from the soil, transports it to its leaves from the soil, transports it to its leaves and hold it there i.e. away from the fruitand hold it there i.e. away from the fruit

This makes the tomatoes more tolerant This makes the tomatoes more tolerant to the high levels of salt in the soil (due to the high levels of salt in the soil (due to modern irrigation techniques)to modern irrigation techniques)

As the tomatoes are more tolerant, it As the tomatoes are more tolerant, it makes it easier to grow in certain makes it easier to grow in certain regions of high salinityregions of high salinity

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How it is doneHow it is done

• A plasmid is removed from Yeast Hal1 A plasmid is removed from Yeast Hal1

• The plasmid is cut open using a restriction The plasmid is cut open using a restriction endonucleaseendonuclease

• The gene to be copied is placed inside the open The gene to be copied is placed inside the open plasmidplasmid

• The gene is pasted into the plasmid using DNA The gene is pasted into the plasmid using DNA ligase. The plasmid is now called a recombinant ligase. The plasmid is now called a recombinant plasmidplasmid

• The vector is placed inside the Yeast Hal1 bacterium The vector is placed inside the Yeast Hal1 bacterium and the bacterium is given its ideal conditions to and the bacterium is given its ideal conditions to grow and proliferategrow and proliferate

Advantages / DisadvantagesAdvantages / Disadvantages

Advantages DisadvantagesSince there is less damage to the maize

crops, there is a higher crop yield which can lessen food shortages.

We are not sure of the consequences of humans and animals eating the modified

crops. Could be harmful to human as well as animal health.

Since there is a higher crop yield, less land is needed to grow more crops. Instead the

land can become an area for wild life conservation.

May tackle, to some extent, world hunger

Other insects which are not harmful to the crops could be killed. The maize pollen will contain the toxin and so if it is blown onto

near by plants it can kill the insects feeding on these plants. 

There is a reduction in the use of pesticides which are expensive and may be harmful to

the environment, wild life and farm workers. 

Cross pollination can occur which results in some wild plants being genetically modified as they contain new gene. These plants will have an advantage over others as they will be resistant to certain insects and so some plants may become endangered. This will

have significant consequences on the population of wild plants. 

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