TRANSGENIC ANIMALS

UNDER GUIDENCE OF :Ms.Meenu SinghM.Pharm(Ph.D.)Asst.ProffesorDept. Pharmacology

By:M.V.PrasanthM.PharmPharmacology

Contents:

Definition Advantages Disadvantages Methods used to produce transgenic animals Examples of Transgenic animals Conclusion

Definition: A Transgenic animal is one

that carries a foreign gene that has been deliberately inserted into its genome.

The foreign gene is constructed using recombinant DNA methodology

Advantages:

Increased growth rate. Improved disease resistance. Improved food conversion rates. Increased muscle mass. Improved nutritional quality. Improved wool quality.

Disadvantages:

Inserted gene has multiple functions. Breeding problems. Sometimes leads to mutagenesis

and functional disorders. Low survival rate of transgenic

animals.

Methods to produce Transgenic animals:

The Embryonic Stem Cell Method.

The Pronucleus Method.

Retro virus mediated gene

transfer.

The Embryonic Stem Cell Method: Embryonic stem cells Formation of gametocytes Injection into blastocysts Injection into foster mother Formation of new individual.

The Pronucleus Method:

Formation of DNA as in the first method. Fusion of male pronucleus with desired

DNA. Formation of diploid zygote. Mitotic division Formation of two-cell embryo. Transferring to foster mother. Formation of new individual.

The image is an comparision between a transgenic mouse and a normal mouse.The giant mouse developed from a fertilized egg transformed with a recombinant DNA molecule containing the Human growth Hormone.

Retro Virus Mediated Gene Transfer: Retroviruses used as vectors to transfer

genetic material into the host cell, resulting in a chimera, an organism consisting of tissues or parts of diverse genetic constitution

Examples for genetically modified animals: Mice Goat Sheep Chicken Cow Horse Dogs Fish

Cats Spiders Guinea pigs Rabbits Rats

Transgenic cows carrying extra copies of two types of casein genes produce 13% more milk protein.

Currently the milk from these animals is under FDA review.

Transgenic Cow:

Advantages: Organ transplant harvesting Study of human membrane

co-factor protein

Enviropig:

Disadvantages: Breeding problem. Mutation will occur. Discharges phytase which is pollutant to

environment.

Transgenic fish:

Tilapia

Salmon/trout

Catfish

Can grow up to 6 times faster than wildtype fish

Most have extra copies of growth hormone (GH) gene

Transgenic sheep:

Tracy is the first transgenic animal to produce a recombinant protein in her milk.

Uses of transgenic sheep: It is used as a model for studying: Immunology Human blood clotting factor viii Transplantation Haematology Biological product manufacturing Recombinant DNA Drug production in milk

Disadvantages: Difficult procedure Failed in vitro fertilization Expensive

Transgenic Mice

Knock-out technology allows for the specific loss of a gene in mice

Advantages: Gene mutation Alzheimer's disease Hypertension Atherosclerosis Cardiac hypertrophy Human leukocyte antigen Human gastric carcinoma Making poliovirus vaccine Different type of cancer HIV studies Ocular inflammation Hepatitis B virus Spinal muscular atrophy (knock-out)

Disadvantages:

• Expensive• Gene can only be added not deleted• Embryos are not easily accessible for

manipulation.

Transgenic Monkey:

Its so similar to human hence it used in clinical trail used for studying :

1. HIV

2. Huntington’s disease Disadvantages:

Expensive Difficult Breeding problem

Transgenic Rabbit:

Alba, the EGFP (enhanced GFP) bunny.

Created in 2000 as a transgenic artwork.

Advantages: Hemorrhagic disease Gene mutation Cell metabolisms Eye disease Heart problems Atherosclerosis Retinal degeneration

Conclusion: Transgenic animals

are now-a-days used for screening of many drugs.

Using of transgenic animals reduce number of experimental animals during testing.