the following file contains information regarding the research based on transgenic animals. It is a biotechnological approach and an assignment(report) of a student of B.S.C second-year biotechnology.

1. TRANSGENIC ANIMALS
SLE US-SBT 301 | MOLECULAR BIOLOGY | RASHMI MA’AM
SHIFA CHOUDHARY | S.Y.B.Sc BT-044 | September 22,2021
INTRODUCTION:
This assignment is about introducing genes into germline of animals and how transgenic
animals can be generated by insertion and integration of foreign genes into the genome of animals
and their transmission to progeny (germline gene transfer). Transgenic technology was primarily
confined to only non-human animals such as mice, domestic animals, etc. for various purposes
like understanding the function of genes or regulatory sequences or for benefit of mankind like
protein expression which have economic importance etc.
WHAT IS TRANSGENIC TECHNOLOGY?
Transgenic technology is the introduction of genes into germline of animals or integration
of these genes into chromosomes of animals so that not only genes is introduced and expressed in
the animal in which we have introduced but the gene is carried through successive generations as
well. So, the offspring generated by the transgenic animal also contain the transgene (carried from
one generation to another). Introduction of appropriate transgene to animals, birds or fish can
achieve useful traits that is beneficial to them or to us. Transgenic tech led to development of fish
and livestock with altered genetic profile that enable them to grow faster, to reduce waste in pigs,
or fight diseases like prion free cows resistant to mad cow disease. We have mouse models for
several types of cancer and human genetic disorders including hepatitis, sickle cell disease, etc.
So, it is also beneficial for developing animal model for a number of diseases
TRANSGENIC ANIMAL
1982 is the landmark in the area of transgenic technology. Credits for development of
transgenic tech goes to two people, Ralph Brinster from University of Pennsylvania US and
Richard Palmiter from University of Washington US. By definition transgenic animal has one or
more foreign genes inserted into its chromosome so that not only gene is carried by the organism,
but also its progeny. For the first time, Brinster and Palmiter actually showed that by expressing a
growth hormone in mouse (transgenic mouse) one can alter the phenotype of mouse and this
phenotypic trait is carried out to future progeny. They introduce the transgene under the control of
a metallothionein promoter into the germline of mice and by feeding these mice with zinc, they
demonstrated that this metallothionein promoter can be turned on by zinc and it turns on growth-
hormone gene. As a result, high level of growth hormones are produced in circulation and high
growth is seen.
They extended the transgenic technology to domestic livestock thereby demonstrating the
potential the potential to enhance growth, modify resistance to disease to disease, and produce
milk containing human proteins of medical importance, such as blood clotting factors for
hemophiliacs and growth hormones. By using this transgenic technology, it became possible to

2. convert animals into bioreactors. Transgenic tech became a very useful tool for mapping or for
identifying spatial and temporal expression of very important promoters.
Transgenic mice are often generated to:
Characterize the ability of a promoter to direct tissue-specific gene expression – a promoter can be
attached to a reporter gene such as LacZ or GFP. Another reason people make transgenic mice is
to examine the effects of overexpressing and mis expressing endogenous or foreign genes at
specific times and locations in the animals.
Green fluorescent protein: This transgenic mouse when a UV light is shine on that, you can see
the entire embryo or the entire mouse, fluorescent green.
Okubo and Hogan (2004) made transgenic mice in which the Wnt signaling pathway was
constitutively activated in the lungs of late embryo. In the resulting transgenic mice, the alveoli of
the lungs are quite abnormal, being composed of large air spaces lined with highly proliferative
cuboidal epithelium. Remarkably, this epithelium contains cells resembling differentiated types
normally found in the intestine rather than lung.
Mighty mice: Transgenic mice with a truncated form of myostatin, increasing muscle mass and
strength, controlled animal models, and so on.
PRODUCTION OF TRANSGENIC ANIMALS
There are many ways to produce transgenic animals:
Microinjection: process of transferring genetic materials into a living cell using micropipettes or
microinjection needles. DNA or RNA is injected directly into the cell's nucleus. In MI a fertilized
egg is taken (with female and male pronucleus) and the egg is held with the holding pipette with
mild vacuum. Then through very fine injection needle, DNA of interest is introduced is inserted
into male pronucleus of the fertilized egg. Survived eggs are then taken and culture and put them
back into the foster mother
Blastocyst injection: will be performed to generate chimeras from one to two mouse ES targeted
clones. This procedure comprises three days of mouse ES cell injection into blastocysts and
transfer of injected embryos into pseudo pregnant foster mice.
Using a retrovirus into the blastocyst so it goes and infect the embryonic stem cells and the gene
gets integrated and can be go into germline and create transgenic mice.
Nuclear transfer
Artificial chromosomes for gene transfer: using sperm as gene transfer vehicle.
REFERENCES:
https://nptel.ac.in/courses/104/108/104108056/