how genetic information transfer to offspring from parents

1. GENE THERAPY
PRESENTED BY- PRIYA CHHIKARA
M. PHARMACY 1ST YEAR (PHARMACOLOGY)
190000803001
DEPARTMENT OF PHARMACEUTICAL SCIENCES
CHAUDHARY BANSI LAL UNIVERSITY
BHIWANI-127021
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2. CONTENTS
Definition
History of gene therapy
Types of gene therapy
Methods of somatic gene therapy
Gene transfer techniques
Clinical applications
Recent development
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3. GENE
Gene is a unit of DNA or segment of DNA
that is usually located on a chromosome
and that controls the development of one or
more traits and is the basic unit by which
genetic information is passed from parent to
offspring.
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4. GENE
THERAPY….
1. It is a corrective therapy for hereditary disease.
2. Gene therapy is collection of methods that allow correction of
a gene defect that has been either diagnosed in child or embryo.
3. Replacing a mutated gene that causes disease with a healthy
copy of the gene.
4. The most common form of gene therapy involves inserting a
normal gene to replace an abnormal gene.
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6. HISTORY OF GENE THERAPY
1960:- the concepts of gene therapy was introduced.
1990:- the first clinical gene therapy is given to 4 years old
girl named “ASHANTI DE SILVA” in September 14,1990 with
ADA (adenosine deaminase) deficiency.
ADA deficiency is one form of SCID ( severe combined
immune
deficiency)
The disease is caused by a mutation(defect) in a gene,
which codes for enzyme adenosine deaminase.
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7. Types of gene therapy
germ-line gene therapy Somatic gene therapy
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10. METHODS OF
SOMATIC
GENE THERAPY
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11. There are mainly two approaches for the transfer of
genes in somatic gene therapy
Somatic gene therapy
In vivo
gene
therapy
Ex vivo
gene
therapy
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12. IN VIVO GENE THERAPY
 Direct delivery of therapeutic gene into target cell into
patient body.
 Carried out by viral and non viral vector systems.
 This is done in case of tissues whose individual cells can’t
be cultured In-vitro in sufficient numbers (e.g Brain cells).
 In-vivo gene transfer is necessary when cultured cells
can’t be re-implanted in patients effectively.
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13. EXAMPLE OF IN-VIVO GENE THERAPY
 In patients with cystic fibrosis, a protein called cystic fibrosis transmembrane
regulator ( CFTR ) is absent due to a gene defect.
 CFTR present on 7th chromosome no.
 In the absence of CFTR chloride ions concentrate within the cells and it draws
water from surrounding.
 This leads to the accumulation of sticky mucous in respiratory tract and lungs
or pancreas and bile duct also.
 Treated by in-vivo replacement of defective gene by Adenovirus vector.
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15. EX VIVO GENE THERAPY
The approach can be applied to the tissues like
hematopoietic cells and skin cells which can be
removed from the body, genetically corrected
outside the body and reintroduced into the
patient body where they become survive for a
long period of time.
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19. GENE TRANSFER TECHNIQUES
1.Transformation
2.Conjugation
3.Electroporation
4.Liposome-mediated gene transfer
5.Transduction
6.Direct transfer of DNA
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20. CONJUGATION
Conjugation is a natural microbial recombination process.
 During conjugation, two live bacteria (a donor and a recipient) come
together, join by cytoplasmic bridges and transfer single stranded DNA (
from donor to recipient).
 Inside the recipient cell, the new DNA may integrate with the chromosome
or may remain free.
 Plasmid insert DNA is transferred from cell to another.
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22. ELECTROPORATION
PRINCIPLE:-
High voltage electric pulses can induce cell plasma membrane to fuse.
Thus, electroporation is technique involving electric field-mediated
membrane permeabilization.
Electric shock can also induce cellular uptake of exogenous DNA from
the suspended solution.
It is a simple and rapid technique for introducing genes into the cells
from various organisms( micro-organisms, plants and animals).
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23. PROCESS
Cells are placed in a solution containing DNA
Subjected to electrical shock to cause holes in the
membrane.
The foreign DNA fragments enter through the holes into the
cytoplasm and then to nucleus.
Advantages:-
Versatile and effective to all
cells.
efficient method
Disadvantages:-
Cell damage.
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25. LIPOSOME-MEDIATED GENE THERAPY
Liposomes are circular lipid molecules, which have an aqueous interior that can carry nucleic acid. Positively charged
liposomes very efficiently complex with DNA, bind to cells and transfer DNA rapidly.
On treatment of DNA fragment with liposomes, the DNA pieces get encapsulated inside liposomes.
These liposomes can adhere to cell membrane and fuse with them to transfer DNA fragments.
DNA enters the cell and then to the nucleus
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27. DIRECT TRANSFER OF DNA
It is possible to directly transfer the DNA into the cell nucleus. Microinjection and particle
bombardment are the two techniques commonly used for this purpose.
Microinjection
Process of using a glass micropipette to insert microscopic substances into a
single living cell.
Normally performed under a specialized optical microscope setup called a
micromanipulator.
Used to create transgenic organisms.
Particle bombardment/ gene gun
No need of virus
Employs a high- pressure delivery system to shoot tissue with gold or tungsten
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30. CLINICAL APPLICATIONS
Gene therapy is being used in many ways.
1. Replace defective genes.
2. Genetic disorder
3. Autoimmune disease:- rheumatoid arthritis
4. Disease involve several genes and the environmental intract:- diabetes
5. Cystic fibrosis
6. SCID( severe combined immunodeficiency) disease
7. Hemophilia
8. Parkinson's disease
9. Cancer
10.Gene therapy cures blindness
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