A transgenic animal is one whose genome has been altered by the transfer of a gene or genes from another species or breed. Methods involved in production of transgenic animals: DNA microinjection Embryonic stem cell-mediated gene transfer and Retrovirus-mediated gene transfer. Applications of Transgenic animals: As disease model Drug and Industrial production Disease control Xenotransplantation Blood replacement  Agriculture As food Transgenic animals are used in toxicity testing. Transgenic animals are used for vaccine testing

1. TRANSGENIC
ANIMALS
By
Koushik Darivemula
M. Sc Biotechnology
Kowshikrishna123@gmail.com

2. A transgenic animal is one whose genome has been altered
by the transfer of a gene or genes from another species or
breed.
Purpose for production of transgenic animals?
For production of recombinant proteins in milk, egg
white, blood, urine, seminal plasma and silk worm
cocoons ( milk and urine found to be best).
 Foreign proteins can be produced in the mammary
glands of transgenic animals .
Used in the laboratory as models in biomedical research.
Used to understand gene function in the context of
disease susceptibility, progression and to determine
responses to a therapeutic intervention (animal model).

3. Transgenic animals: timeline of key events:
https://drive.google.com/file/d/1E178Z5KmC_QleX8wJM-
acjel5i8lnC7z/view?usp=sharing
Methods involved in production of transgenic animals:
1. DNA microinjection
2. Embryonic stem cell-mediated gene transfer and
3. Retrovirus-mediated gene transfer.
Steps involved in production of Transgenic animals:
a. Construction of transgene
b. Introduction of foreign gene into the animal
c. Screening of transfection efficiency
d. Animal breeding to obtain maximal expression.

4. 1. Transgenic construct involves assembling three basic DNA elements:
A. A promoter and/or enhancer which confers the desired spatial and
temporal pattern of transgene expression;
B. The gene to be transcribed, which may or may not encode a protein; and
C. A transcription termination or polyadenylation signal sequence to stop
transcription and enable 3′ end processing.
2. Introduction of foreign gene into the animal:
a) Microinjection
b) Retrovirus-mediated gene transfer.
c) Embryonic stem cell-mediated gene transfer and

5. Other methods involved:
Spermatogonia manipulation
somatic cell nuclear
transplantation
Cre-lox technique

6. 3. Screening of transfection efficiency:
a) Polymerase chain reaction (PCR) to examine the site of insertion of
gene.
b) Genes are not expressed when inserted in transcriptionally inactive site.
4. Animal breeding to obtain maximal expression:
Heterozygous offspring's are mated to form homozygous strains.
Steps involved in production of Transgenic animals

7. Examples of Transgenic animals:
a. Transgenic mouse
b. Transgenic sheep
c. Transgenic fish
d. Transgenic monkey
e. Transgenic pig
Animal model for studies
on many diseases:
• Alzheimer’s
mouse
• Oncomouse
• Smart mouse

8. Transgenic sheep:

9. Transgenic fish were
developed using a variety
of transgenes, methods,
and species since the
first transgenic fish were
produced in China in
1985.

10. Applications of Transgenic animals:
• As disease model
• Drug and Industrial production
• Disease control
• Xenotransplantation
• Blood replacement
• Agriculture
• As food
• Transgenic animals are used in toxicity testing.
• Transgenic animals are used for vaccine testing.
Problems:
 Multiple insertions – Too much proteins
 Insertion into an Essential gene – Lethality
 Insertion into a gene leading to gene silencing
 Insertion into a different area leads to gene regulation.

11. 1. https://www.whatisbiotechnology.org/index.php/science/summary/trans
genic/transgenic-animals-have-genes-from-other-species-inserted
2. https://people.ucalgary.ca/~browder/transgenic.html
3. https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3815551/#:~:text=Gene
rating%20a%20typical%20transgenic%20construct,3)%20a%20transcription%
20termination%20or
4. https://www.tandfonline.com/doi/full/10.1080/23311932.2019.1686802
5. https://ijpsr.com/bft-article/transgenic-animals-production-and-
application/?view=fulltext#:~:text=Transgenic%20animals%20are%20produ
ced%20as,of%20genes%20in%20specific%20diseases.