gene therapy, vectors

1. By,
D.Akshaya
B.GOKULA PRIYA

2.  GENE THERAPY-
DEFINITION
 HISTORY-GENE
THERAPY
 TECHNIQUES AND
TERMS
 TYPES OF GENE
THERAPY
 ADVANTAGES AND
DISADVANTAGES
 CONCLUSION

3. Gene therapy is the use
of DNA as a
pharmaceutical agent
to treat disease.

4.  DNA: Genes are composed of DNA, a molecule in the
memorable shape of a double helix, a spiral ladder. Each
rung of the spiral ladder consists of two paired chemicals
called bases. There are four types of bases. They are
adenine (A), thymine (T), cytosine (C), and guanine (G). As
indicated, each base is symbolized by the first letter of its
name: A, T, C, and G. Certain bases always pair together
(AT and GC). Different sequences of base pairs form coded
messages.
 The gene: A gene is a sequence (a string) of bases. It is
made up of combinations of A, T, C, and G. These unique
combinations determine the gene's function, much as
letters join together to form words. Each person has
thousands of genes -- billions of base pairs of DNA or bits
of information repeated in the nuclei of human cells --
which determine individual characteristics (genetic traits).

5.  The concepts of gene therapy arose
initially during the 1960s and early 1970s
….
 With the arrival of recombinant DNA
techniques, cloned genes became available
 Efficient retroviral vectors and other gene
transfer methods have permitted
convincing demonstrations of efficient
phenotype correction in vitroand in vivo,
now making gene therapy a broadly
accepted approach to therapy

6. PICTORIAL REPRESENTATION..

7.  Cells from the patient’s blood or bone marrow are
removed (usually cells containing defective genes)
 The cells are exposed to viruses,carrying the desired
genes…
 Then,the cells are grown in the laboratory and then
injected into the patient’s body.

9.  Viral method-uses viral
vectors for gene
transfer…
 Method: Viruses are
first disabled to
replicate themselves
and are exposed to the
cells
 Drawback:possiblities
for vial multiplication-
leads to new diseases..
 NON-VIRAL METHODS
 Electroporation-
electric field
 Sonoporation-
ultasonic frequencies
 Gene gun-
bombardment
 Magnetofection-
magnetic field

11.  SOMATIC -gene
therapy
 Gene transfer to
somatic cells…
 The effect is not
hereditary i.e
confined to the
individual
 GERM LINE-gene
therapy
 Gene transfer to
germ cells
viz..sperm or egg
 The effect is
hereditary

12. Genetic disorders
 Severe Combined
Immune Deficiency
 Chronic Granulomatus
Disorder
 Hemophilia
Acquired diseases
 Cancer
 Neurodegenerative
diseases
 HIV

13. Advantages
arrests some diseases
 gives patients new genes, so
they don't have the disease and
the disease doesn't come back
 provides as a way of treatment
when in the past the disease
would have been incurable
 there have been
several medical breakthroughs
 some people consider it a
great advancement for
mankind
Disadvantages
In the past, gene therapy
has cured some diseases,
but caused others
 Its inconsistent
 Its a fairly new method, so
there are still
some glitches to it that
scientists are still figuring
out.
 some people are against
the ethics of it: some say
its "playing God"
 the patient may have to
undergo several therapy
treatments

14.  GENE-THERAPY is an upcoming field and in
the future i.e within a decade its going to be
the cure for every genetic disease and the
other methods would go a cliche!!