Download Gene Therapy by calisa and carmen

GENE
THERAPY
By: Carmen Nahous & Calisa Lakhan
What is a gene?
~A gene is the basic unit of heredity in a living
organism that determines physical traits.
~They are found on particular loci (positions) of
chromosomes.
~Your cells use the information from your genes to
manufacture proteins that do the work in your body.
~Genes contain your DNA.
.
What is Gene Therapy?
~Gene therapy involves altering the genes inside your
body’s cells to stop diseases, by replacing a faulty gene or
adding a new gene in an attempt to cure a disease or make
changes in the body so that it is better able to combat
diseases.
~Gene therapy holds promise for
treating a wide range of diseases
including cancer, cystic fibrosis, heart
disease, diabetes, hemophilia and AIDS.
Why is Gene Therapy done?
Replace missing or mutated genes
This is currently the most common gene therapy approach. Some cells
become diseased because some genes have been permanently switched off.
Other cells may be missing certain genes. Researchers hope that replacing
missing or defective genes can help treat certain diseases.
Changing the regulation of a gene
Mutated genes that cause diseases
could be turned off or healthy genes that
prevent diseases could be turned on so that
they can inhibit the disease.
Making diseased cells more evident to the immune system
The immune system does not always attack the diseased cells
because they are not recognized as intruders. Using gene therapy, doctors
could potentially infuse mutated cells with genes that make them more
recognizable to the immune system.
Risks associated with Gene Therapy
Gene therapy poses a number of risks. A gene can’t
simply be inserted directly into the cell. It usually has to be
delivered using a carrier, called a vector. Commonly used as
vectors are viruses because they can recognise certain cells
and carry genetic material into the cells genes.
~This technique presents the following risks:
Immune response
The body’s immune system may see
the newly introduced viruses as intruders
and attack them.
Viral Spread
Because viruses can affect more than one type of cell, it
is possible that the viral vectors may infect cells in addition to
the ones for which they were intended – just those containing
mutated or missing genes. If this happens, healthy cells may be
damaged, causing other illnesses or diseases, including cancer.
Possibility of Inducing a Tumor
If the new genes get inserted in the
wrong spot in the genome, there is a
chance that the insertion might lead to a
tumor formation.
Conclusion
The possibilities of gene therapy hold much promise. To
date however, that promise has not been realised. Some clinical
trials have recorded small successes for a few participants. But
several significant barriers stand in the way of gene therapy
becoming a reliable form of treatment. The barriers include
developing reliable vectors, consistently ensuring safety, targeting
the correct cells and preventing genetic changes from being
passed on from parent to child.
Although at this time no clinical trial
has been seen as a breakthrough in overcoming all
these barriers, gene therapy is a very active
area of research. Researchers hope that with
continued study, advances in gene therapy
will eventually make it a practical approach
to treating diseases.