The document summarizes topics related to transgenic animals and gene therapy. It discusses transgenic cows, sheep, poultry, and fish. For each animal, it describes the process used to create transgenic versions, including pronuclear microinjection and somatic cell nuclear transfer. Benefits include producing human therapeutic proteins and altering milk composition. Challenges include high costs and low success rates. Gene therapy techniques like viral vectors and electroporation are explained for inserting genes into tissues to treat disease. Somatic gene therapy aims to modify individual patients while germline gene therapy alters heritable genes passed to offspring.
Introduction
History
Landmarks Events in Transgenic Livestock Research
Techniques/ Method for Gene Transfer
Examples of transgenesis
Importance
Application
Limitation
Issue related to Transgenic Technology
Ethical concerns and how to Overcome
A knockout mouse is a mouse in which a specific gene has been inactivated or“knocked out” by replacing it or disrupting it with an artificial piece of DNA.
The loss of gene activity often causes changes in a mouse's phenotype and thus provides valuable information on the function of the gene.
Sheep named Dolly was cloned by transfer of a nucleus from a mammary (Udder) cell of an adult sheep into an egg cell.
mammary cell
Nucleus
insert into
a egg cell
First demonstration of pluripotency (totipotency) of a nucleus of a differentiated adult cell.
Cloning of dolly somatic cell nuclei
clone cattle, sheep, goats, pigs.
nuclear transfer procedures are similar.
Adult donor cells from a variety of cell types(mammary epithelial and ovarian cells, fibroblasts, lymphocytes) are isolated
Cultured and genetically modified methods.
individual donor cells are fused to an enucleated oocyte with short-duration electric pulse.
eg: two 2.5 kilovolt /cm pulses for 10microseconds
Used to fuse adult cattle fibroblasts with enucleated oocytes.
The pulses simultaneously induce cell fusion and oocyte activation.
Blastocyst stage before transferred into the uterus of a pseudopregant female.
Confirmed transgene at the time of birth
Surviving animals produced by nuclear transfer are healthy.
There, is a substantial loss of individual before and after birth some of the cloned animals display abnormalities.
Abnormlities such as increased birth weight.
Dna methylation and histone modification of the original donor cell is inappropriate maintained in the cells of the recipient animals.
Introduction.
Definition.
Importance of transgenic animals.
Transgenic mice
Methods for introducing a foreign gene:
The retroviral vector method
The DNA microinjection method/ pronuclear microinjection
Genetically engineered embryonic stem cells
Transgenic fish
What is transgenic fish?
A few facts to know to know about transgenic fish.
Important points needed for genetic engineering (gene transfer) to produce transgenic fish.
Development of transgenic fishes.
A few examples
Auto-transgenesis.
Controlled culture of transgenic fish and feed.
Gene transfer technology for development of transgenic fishes.
Gene flow.
Food safety issues.
Conclusion.
Bibliography.
Introduction
Definition
History
Why are the transgenic animals being produced
Transgenic mice
Mice: as model organism
Methods of creation of transgenic mice
knock-out mice
Application of transgenic mice
Conclusion
References
Introduction
History
Landmarks Events in Transgenic Livestock Research
Techniques/ Method for Gene Transfer
Examples of transgenesis
Importance
Application
Limitation
Issue related to Transgenic Technology
Ethical concerns and how to Overcome
A knockout mouse is a mouse in which a specific gene has been inactivated or“knocked out” by replacing it or disrupting it with an artificial piece of DNA.
The loss of gene activity often causes changes in a mouse's phenotype and thus provides valuable information on the function of the gene.
Sheep named Dolly was cloned by transfer of a nucleus from a mammary (Udder) cell of an adult sheep into an egg cell.
mammary cell
Nucleus
insert into
a egg cell
First demonstration of pluripotency (totipotency) of a nucleus of a differentiated adult cell.
Cloning of dolly somatic cell nuclei
clone cattle, sheep, goats, pigs.
nuclear transfer procedures are similar.
Adult donor cells from a variety of cell types(mammary epithelial and ovarian cells, fibroblasts, lymphocytes) are isolated
Cultured and genetically modified methods.
individual donor cells are fused to an enucleated oocyte with short-duration electric pulse.
eg: two 2.5 kilovolt /cm pulses for 10microseconds
Used to fuse adult cattle fibroblasts with enucleated oocytes.
The pulses simultaneously induce cell fusion and oocyte activation.
Blastocyst stage before transferred into the uterus of a pseudopregant female.
Confirmed transgene at the time of birth
Surviving animals produced by nuclear transfer are healthy.
There, is a substantial loss of individual before and after birth some of the cloned animals display abnormalities.
Abnormlities such as increased birth weight.
Dna methylation and histone modification of the original donor cell is inappropriate maintained in the cells of the recipient animals.
Introduction.
Definition.
Importance of transgenic animals.
Transgenic mice
Methods for introducing a foreign gene:
The retroviral vector method
The DNA microinjection method/ pronuclear microinjection
Genetically engineered embryonic stem cells
Transgenic fish
What is transgenic fish?
A few facts to know to know about transgenic fish.
Important points needed for genetic engineering (gene transfer) to produce transgenic fish.
Development of transgenic fishes.
A few examples
Auto-transgenesis.
Controlled culture of transgenic fish and feed.
Gene transfer technology for development of transgenic fishes.
Gene flow.
Food safety issues.
Conclusion.
Bibliography.
Introduction
Definition
History
Why are the transgenic animals being produced
Transgenic mice
Mice: as model organism
Methods of creation of transgenic mice
knock-out mice
Application of transgenic mice
Conclusion
References
Introduction.
Properties of Stem Cells.
Key Research events.
Embryonic Stem Cell.
Stem cell Cultivation.
Stem cells are central to three processes in an organism.
Research & Clinical Application of stem cell.
Research patents.
Conclusion.
Reference.
a proper description about the process microinjection and also about gene transfer. and different types of DNA delivery methods.
with advantages, disadvantages, limitations and applications.
it contain some production techniques of transgenic animals with some examples and utility in drug development (available transgenic animals model of drug and their activity).
Applications and uses in different field
Another techniques like transposons and knock-out & knock-in discussed later
This presentation aims to provide an in-depth understanding of the science behind creating transgenic animals, explore their potential applications, and delve into the ethical considerations surrounding this emerging field of research.
Definition and Background:
We begin by defining transgenic animals as organisms that have had their genetic material intentionally altered through the introduction of foreign genes. This groundbreaking field of genetic engineering has its roots in the development of recombinant DNA technology in the 1970s, which enabled the transfer of genes across different species.
Genetic Engineering Techniques:
This section delves into the techniques employed to create transgenic animals, emphasizing the following key methodologies:
a. DNA Microinjection: The introduction of foreign DNA into the pronucleus of a fertilized embryo, allowing the foreign gene to be incorporated into the animal's genome and expressed in its cells.
b. Gene Targeting: The precise modification of an organism's genome by replacing or disrupting specific genes using technologies such as homologous recombination or CRISPR-Cas9.
c. Somatic Cell Nuclear Transfer (SCNT): The cloning technique involving the transfer of a nucleus from a somatic cell into an enucleated egg, resulting in the creation of an embryo with the same genetic makeup as the somatic cell donor.
Applications of Transgenic Animals:
This section explores the wide-ranging applications of transgenic animals across various fields, including:
a. Biomedical Research: Transgenic animals serve as invaluable models for studying human diseases and testing potential therapies, enabling significant advancements in medical research.
b. Agriculture: Transgenic animals can be engineered to possess desirable traits, such as increased resistance to diseases or improved meat quality, offering the potential to enhance agricultural productivity and sustainability.
c. Pharmaceutical Production: Transgenic animals can be designed to produce therapeutic proteins or antibodies in their milk or blood, providing a cost-effective means of manufacturing valuable pharmaceutical products.
d. Organ Transplantation: Research on transgenic animals has explored the possibility of generating organs that are genetically compatible with humans, addressing the shortage of donor organs for transplantation.
Introduction.
Properties of Stem Cells.
Key Research events.
Embryonic Stem Cell.
Stem cell Cultivation.
Stem cells are central to three processes in an organism.
Research & Clinical Application of stem cell.
Research patents.
Conclusion.
Reference.
a proper description about the process microinjection and also about gene transfer. and different types of DNA delivery methods.
with advantages, disadvantages, limitations and applications.
it contain some production techniques of transgenic animals with some examples and utility in drug development (available transgenic animals model of drug and their activity).
Applications and uses in different field
Another techniques like transposons and knock-out & knock-in discussed later
This presentation aims to provide an in-depth understanding of the science behind creating transgenic animals, explore their potential applications, and delve into the ethical considerations surrounding this emerging field of research.
Definition and Background:
We begin by defining transgenic animals as organisms that have had their genetic material intentionally altered through the introduction of foreign genes. This groundbreaking field of genetic engineering has its roots in the development of recombinant DNA technology in the 1970s, which enabled the transfer of genes across different species.
Genetic Engineering Techniques:
This section delves into the techniques employed to create transgenic animals, emphasizing the following key methodologies:
a. DNA Microinjection: The introduction of foreign DNA into the pronucleus of a fertilized embryo, allowing the foreign gene to be incorporated into the animal's genome and expressed in its cells.
b. Gene Targeting: The precise modification of an organism's genome by replacing or disrupting specific genes using technologies such as homologous recombination or CRISPR-Cas9.
c. Somatic Cell Nuclear Transfer (SCNT): The cloning technique involving the transfer of a nucleus from a somatic cell into an enucleated egg, resulting in the creation of an embryo with the same genetic makeup as the somatic cell donor.
Applications of Transgenic Animals:
This section explores the wide-ranging applications of transgenic animals across various fields, including:
a. Biomedical Research: Transgenic animals serve as invaluable models for studying human diseases and testing potential therapies, enabling significant advancements in medical research.
b. Agriculture: Transgenic animals can be engineered to possess desirable traits, such as increased resistance to diseases or improved meat quality, offering the potential to enhance agricultural productivity and sustainability.
c. Pharmaceutical Production: Transgenic animals can be designed to produce therapeutic proteins or antibodies in their milk or blood, providing a cost-effective means of manufacturing valuable pharmaceutical products.
d. Organ Transplantation: Research on transgenic animals has explored the possibility of generating organs that are genetically compatible with humans, addressing the shortage of donor organs for transplantation.
It's include all the details about the transgenic technology.all the techniques like micro injection,SCNT,pro nuclear injection method.It include all the Transgenic mice bird and fish.
Transgenic Animals developement and uses(M.NAGAPRADHEESH).pptxMNAGAPRADHEESH
DEVELOPEMENT AND USES OF TRANSGENIC ANIMALS:
■Definitions about Transgenic Animals (or) Genetically Modified Animals(GMO).
■History and Developements of Transgenic Animals(Yearwise:1907-2017)
■Different Methods used for developement of Transgenic animals:
1.Microinjection Method
2.Retro Viral Method
3.Embryonic Stem cell method
■Applications of Transgenic Animals
■Advantages of Transgenic Animals
■Disadvantages of Transgenic Animals
■References.
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This is about methods of creating transgenic animals,applications of transgenic animals in biotechnology and application of transgenic animals in pharmaceuticals.
The Roman Empire A Historical Colossus.pdfkaushalkr1407
The Roman Empire, a vast and enduring power, stands as one of history's most remarkable civilizations, leaving an indelible imprint on the world. It emerged from the Roman Republic, transitioning into an imperial powerhouse under the leadership of Augustus Caesar in 27 BCE. This transformation marked the beginning of an era defined by unprecedented territorial expansion, architectural marvels, and profound cultural influence.
The empire's roots lie in the city of Rome, founded, according to legend, by Romulus in 753 BCE. Over centuries, Rome evolved from a small settlement to a formidable republic, characterized by a complex political system with elected officials and checks on power. However, internal strife, class conflicts, and military ambitions paved the way for the end of the Republic. Julius Caesar’s dictatorship and subsequent assassination in 44 BCE created a power vacuum, leading to a civil war. Octavian, later Augustus, emerged victorious, heralding the Roman Empire’s birth.
Under Augustus, the empire experienced the Pax Romana, a 200-year period of relative peace and stability. Augustus reformed the military, established efficient administrative systems, and initiated grand construction projects. The empire's borders expanded, encompassing territories from Britain to Egypt and from Spain to the Euphrates. Roman legions, renowned for their discipline and engineering prowess, secured and maintained these vast territories, building roads, fortifications, and cities that facilitated control and integration.
The Roman Empire’s society was hierarchical, with a rigid class system. At the top were the patricians, wealthy elites who held significant political power. Below them were the plebeians, free citizens with limited political influence, and the vast numbers of slaves who formed the backbone of the economy. The family unit was central, governed by the paterfamilias, the male head who held absolute authority.
Culturally, the Romans were eclectic, absorbing and adapting elements from the civilizations they encountered, particularly the Greeks. Roman art, literature, and philosophy reflected this synthesis, creating a rich cultural tapestry. Latin, the Roman language, became the lingua franca of the Western world, influencing numerous modern languages.
Roman architecture and engineering achievements were monumental. They perfected the arch, vault, and dome, constructing enduring structures like the Colosseum, Pantheon, and aqueducts. These engineering marvels not only showcased Roman ingenuity but also served practical purposes, from public entertainment to water supply.
The Indian economy is classified into different sectors to simplify the analysis and understanding of economic activities. For Class 10, it's essential to grasp the sectors of the Indian economy, understand their characteristics, and recognize their importance. This guide will provide detailed notes on the Sectors of the Indian Economy Class 10, using specific long-tail keywords to enhance comprehension.
For more information, visit-www.vavaclasses.com
Read| The latest issue of The Challenger is here! We are thrilled to announce that our school paper has qualified for the NATIONAL SCHOOLS PRESS CONFERENCE (NSPC) 2024. Thank you for your unwavering support and trust. Dive into the stories that made us stand out!
Ethnobotany and Ethnopharmacology:
Ethnobotany in herbal drug evaluation,
Impact of Ethnobotany in traditional medicine,
New development in herbals,
Bio-prospecting tools for drug discovery,
Role of Ethnopharmacology in drug evaluation,
Reverse Pharmacology.
Synthetic Fiber Construction in lab .pptxPavel ( NSTU)
Synthetic fiber production is a fascinating and complex field that blends chemistry, engineering, and environmental science. By understanding these aspects, students can gain a comprehensive view of synthetic fiber production, its impact on society and the environment, and the potential for future innovations. Synthetic fibers play a crucial role in modern society, impacting various aspects of daily life, industry, and the environment. ynthetic fibers are integral to modern life, offering a range of benefits from cost-effectiveness and versatility to innovative applications and performance characteristics. While they pose environmental challenges, ongoing research and development aim to create more sustainable and eco-friendly alternatives. Understanding the importance of synthetic fibers helps in appreciating their role in the economy, industry, and daily life, while also emphasizing the need for sustainable practices and innovation.
Operation “Blue Star” is the only event in the history of Independent India where the state went into war with its own people. Even after about 40 years it is not clear if it was culmination of states anger over people of the region, a political game of power or start of dictatorial chapter in the democratic setup.
The people of Punjab felt alienated from main stream due to denial of their just demands during a long democratic struggle since independence. As it happen all over the word, it led to militant struggle with great loss of lives of military, police and civilian personnel. Killing of Indira Gandhi and massacre of innocent Sikhs in Delhi and other India cities was also associated with this movement.
The French Revolution, which began in 1789, was a period of radical social and political upheaval in France. It marked the decline of absolute monarchies, the rise of secular and democratic republics, and the eventual rise of Napoleon Bonaparte. This revolutionary period is crucial in understanding the transition from feudalism to modernity in Europe.
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2024.06.01 Introducing a competency framework for languag learning materials ...Sandy Millin
http://sandymillin.wordpress.com/iateflwebinar2024
Published classroom materials form the basis of syllabuses, drive teacher professional development, and have a potentially huge influence on learners, teachers and education systems. All teachers also create their own materials, whether a few sentences on a blackboard, a highly-structured fully-realised online course, or anything in between. Despite this, the knowledge and skills needed to create effective language learning materials are rarely part of teacher training, and are mostly learnt by trial and error.
Knowledge and skills frameworks, generally called competency frameworks, for ELT teachers, trainers and managers have existed for a few years now. However, until I created one for my MA dissertation, there wasn’t one drawing together what we need to know and do to be able to effectively produce language learning materials.
This webinar will introduce you to my framework, highlighting the key competencies I identified from my research. It will also show how anybody involved in language teaching (any language, not just English!), teacher training, managing schools or developing language learning materials can benefit from using the framework.
2. What is Gene transfer ?
The insertion of unrelated genetic information in the form of DNA into cells. Some of
these
methods involve the use of a vector such as a virus that has been specifically modified so
it can take the gene along with it when it enters the cell.
What is Transgenic animal ?
Transgenic animals are animals (most commonly mice) that have had a foreign gene
deliberately inserted into their genome. Such animals are most commonly created by the
microinjection of DNA into the pronuclei of a fertilized egg which is subsequently
implanted into the oviduct of a pseudo pregnant surrogate mother.
3. Definition- A transgenic animal is one whose genome has been altered by the transfer of a
gene or genes from another species or breed.
Discovery- The first successful transfer of embryos was achieved by Walter Heape in Angora
in
1891.
The first genetic modification of animals was reported in
1974 by the virologist Rudolph Jaenisch, then at the
Salk Institute,
The photo of two transgenic mice positioned either side of a plain mouse. The transgenic mice
have been genetically modified so that they carry a green fluorescent protein which glows green
under blue light.
4. Importance-
Transgenic animals are routinely used in the laboratory as models in biomedical research.
They are important tools for researching human disease, being used to understand gene
function in the context of disease susceptibility, progression and to determine responses to a
therapeutic intervention.
Transgenic farm animals are also being explored as a means to produce large quantities of
complex human proteins for the treatment of human disease. Such therapeutic proteins are
currently produced in mammalian cell-based reactors.
A cheaper option would be to develop a means to produce recombinant proteins in the milk,
blood or eggs of transgenic animals.
The first is human antithrombin III, a therapeutic protein produced in the milk of transgenic
goats, which is used to prevent clots in patients with hereditary antithrombin deficiency
receiving surgery or undergoing childbirth.
5. A recombinant human C12 esterase inhibitor produced in the milk of transgenic rabbits. This is
used to treat hereditary angioedema, a rare genetic disorder which causes blood vessels in the
blood to expand and cause skin swellings.
Disadvantage- a) Transgenic animal project is extremely expensive.
b) Generation of transgenic animals are also expensive, because of long gestation
period, litter size and higher maintenance cost of the recipient animals.
c) Large number of recipients is required for embryo transfer because of low
transgenesis rate.
d) Transgenic foods have been produced and offer better productivity in terms of
both yield and quantity. However, there are some apprehension about the
safety
of transgenic foods.
6. Transgenic cow
Definition- Transgenic cows are genetically modified (GM) cows.
They have an extra gene or genes inserted into their DNA.
The extra gene may come from the same species or
from a different species.
Techniques used to make transgenic cows- Making a transgenic cow is a multi-step process.
1. First, the gene for the desired product is identified and sequenced. Then a gene
construct containing this desired gene is created using DNA cloning, restriction
enzyme digests and ligation.
2. The gene construct is then introduced into female bovine (cow) cells by
transfection
3. Transgenic bovine cells are selected and fused with bovine oocytes that have had
all of their chromosomes removed.
7. 4. Once fused with the oocyte, the transgenic cell’s chromosomes are
reprogrammed to direct development into an embryo, which can be implanted
into a recipient cow.
5. After a 9-month gestation period, a female calf is born. She will only express
the
transgene in her milk during lactation after her first calf is born. This is
because
expression of the transgene is controlled by a promoter specific to lactating
mammary cells.
This article gives further information on the techniques used to make transgenic cows.
Advantages- 1. Making therapeutic proteins
Transgenic cows can be used as ‘bio factories’ to produce human therapeutic
proteins (proteins that are used to treat diseases).
8. At AgResearch, they’ve generated cows that produce human myelin basic protein.
Treatment with human myelin basic protein may help reduce the symptoms of
multiple
sclerosis.
2. Making functional foods
Milk composition can be altered to make a functional food. For example, researchers
have shown that minor proteins in milk (such as lactoferrin) could protect humans
against infection and improve gut health.
3. Hypo-allergenic milk
In 2012, the AgResearch team published the news that they had bred the first cow
in
the world to produce milk with reduced amounts of beta-lactoglobulin (BLG). BLG
is a
milk protein largely responsible for infants’ allergic reactions to cow’s milk.
9. Transgenic sheep
Definition- In sheep, pronuclear microinjection of several hundred
copies of the foreign gene into embryos is the only published
method used to regularly produce transgenic sheep.
Procedure to making Transgenic sheep-
1. Individual donor cells are fused to an enucleated oocyte with short-duration electric pulse.
2. e.g.: two 2.5 kilovolt /cm pulses for 10microseconds.
3. Used to fuse adult cattle fibroblasts with enucleated oocytes.
4. The pulses simultaneously induce cell fusion and oocyte activation.
5. Blastocyst stage before transferred into the uterus of a pseudopregant female.
6. Confirmed transgene at the time of birth.
10.
11. 7. Surviving animals produced by nuclear transfer are healthy.
8. There, is a substantial loss of individual before and after birth some of the cloned animals
display abnormalities.
9. Abnormalities such as increased birth weight.
10. DNA methylation and histone modification of the original donor cell is inappropriate
maintained in the cells of the recipient animals.
Advantages- 1. Site-specific genetic changes are possible
2. All offspring are transgenic In DNA microinjection,
Limitation- 1. transgene integration occurs at random sites
2. Unstable things are formed
3. Expression is always constrained(limit)
4. No. of generations required
12. Transgenic poultry
Definition- In addition to retroviral vectors, microinjection of
DNA has been demonstrated to produce transgenic
poultry. Injection of DNA into the pronucleus of the
newly fertilized egg is a common procedure for the
production of transgenic
14. Transgenic fish
Definition- A transgenic fish is one that contains genes from another species.
A transgenic fish is an improved variety of fish provided with one
or more desirable foreign gene for the purpose of enhancing
fish quality, growth, resistance and productivity.
Method to production of Transgenic fish-
1. Microinjection method:
Microinjection method has been used successfully in the production of transgenic fish and is
a
commonly used technique due to its simplicity and reliability. Microinjection that allows
delivery of the transgene directly into the nucleus, Transgene is directly microinjected into
the
male pronuclei of fertilized eggs.
15. 2. Electroporation method:
Electroporation has been shown to be the most effective means of gene transfer in fish since a
large number of fertilized eggs can be treated in a short time by this method.
Electroporation utilizes a series of short electric pulses to permeate the cell membrane that
make possible the formation of temporary pores on the surface of the target cells through
which the transgene is introduced into the cytoplasm where it is then delivered to the
nucleus
by the cellular machinery.
3. Sperm mediated gene transfer method:
Spermatozoa are capable of binding DNA and carrying it into an egg. Fish spermatozoa can
be
stored in seminal plasma with little loss of viability for long periods. Therefore, this
technique
16. 4. Retroviral infection method:
The successful use of Retroviruses for gene delivery in fish has been reported.
Advantage of Transgenic fish-
1. Transgenic fish have been developed for applications such as the production of human
therapeutics, experimental models for biological research, environmental monitoring, ornamental
fish and aqua cultural production.
2. Growth enhanced transgenic fish have improved feed-conversion efficiency, resulting in
economic and potential environmental benefits such as reduced feed waste and effluent from fish
farms.
3. Transgenic strains provide useful model systems for studying the consequences of growth
enhancement from genetic, physiological and ecological standpoints.
4. Commercial production of transgenic fish able to transmit desirable characteristics, such as
enhanced growth or disease resistance to their progeny.
17. Gene Therapy
Definition- Gene therapy is the insertion of genes into an individual's cells and tissues to
treat a disease, and hereditary diseases in which a defective mutant allele is replaced
with a functional one.
Classification- Gene therapy may be classified into two types:
1. Somatic:
In somatic cell gene therapy (SCGT), the therapeutic genes are transferred into any cell
other than a gamete, germ cell, gametocyte, or undifferentiated stem cell. Any such
modifications affect the individual patient only, and are not inherited by offspring.
Somatic gene therapy represents mainstream basic and clinical research, in
which therapeutic DNA (either integrated in the genome or as an external episome or
plasmid) is used to treat disease.
18. 2. Germline:
In germline gene therapy (GGT), germ cells (sperm or egg cells) are modified by the introduction of
functional genes into their genomes.
Modifying a germ cell causes all the organism's cells to contain the modified gene. The
change is therefore heritable and passed on to later generations.
Vectors- Vectors in gene therapy
The delivery of DNA into cells can be accomplished by multiple methods. The two major classes are
recombinant viruses (sometimes called biological nanoparticles or viral vectors) and naked DNA or
DNA complexes (non-viral methods).
1. Viral vectors: In order to replicate, viruses introduce their genetic material into the host cell,
tricking the host's cellular machinery into using it as blueprints for viral
proteins.
Retroviruses go a stage further by having their genetic material copied into the
genome of the host cell.
19. A number of viruses have been used for human gene therapy, including retroviruses,
adenoviruses, herpes simplex, vaccinia, and adeno-associated virus.
2. Non-viral vectors: Non-viral methods present certain advantages over viral methods, such
a large scale production and low host immunogenicity.
Methods for non-viral gene therapy include the injection of naked DNA, electroporation, the gene
gun, sonoporation, magnetofection, the use of oligonucleotides, lipoplexes, dendrimers, and
inorganic nanoparticles immunogenicity.
• Injection of naked DNA- It is the process to inject the naked DNA in to the skeletal muscle and
produce a lot of excitement and lead to the possibility or using the gene as vaccines.
• Electrophoration- The last few years has seen a marked increase in the number of studies
employing intramuscular or intradermal injection of naked DNA followed by electroporation.
20. Gene gun- In genetic engineering, a gene gun or a biolistic particle delivery system, originally
designed for plant transformation, is a device for delivering exogenous DNA (transgenes) to
cells. The payload is an elemental particle of a heavy metal coated with DNA (typically plasmid
DNA).
Lipoplex- Plasmid DNA can be covered with lipids in an organized structure like a micelle or a
liposome. When the organized structure is complexed with DNA it is called a lipoplex. There
are three types of lipids, anionic (negatively charged), neutral, or cationic (positively charged).
Initially, anionic and neutral lipids were used for the construction of lipoplexes for synthetic
vectors.
Sonoporation- Sonoporation, or cellular sonication, is the use of sound (ultrasonic frequencies)
for modifying the permeability of the cell plasma membrane. This technique is usually used in
molecular biology and non-viral gene therapy in order to allow uptake of large molecules such
as DNA into the cell, in a cell disruption process called transfection or transformation.
Sonoporation is under active study for the introduction of foreign genes
in
tissue culture cells, especially mammalian cells.