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In the not so distant future, genetic engineering will become a principal
player in fighting genetic, bacterial, and viral disease, along with controlling
aging, and providing replaceable parts for humans. Medicine has seen many new
innovations in its history. The discovery of anesthetics permitted the birth of
modern surgery, while the production of antibiotics in the 1920s minimized the
threat from diseases such as pneumonia, tuberculosis and cholera. The creation
of serums which build up the bodies immune system to specific infections, before
being laid low with them, has also enhanced modern medicine greatly (Stableford
59). All of these discoveries will fall under the broad shadow of genetic
engineering when it reaches its apex in the medical community. Many people
suffer from genetic diseases ranging from thousands of types of cancers, to
blood, liver, and lung disorders. Amazingly, all of these will be able to be
treated by genetic engineering, specifically, gene therapy. The basis of gene
therapy is to supply a functional gene to cells lacking that particular
function, thus correcting the genetic disorder or disease. There are two main
categories of gene therapy: germ line therapy, or altering of sperm and egg
cells, and somatic cell therapy, which is much like an organ transplant. Germ
line therapy results in a permanent change for the entire organism, and its
future offspring.
Unfortunately, germ line therapy, is not readily in use on humans for ethical
reasons. However, this genetic method could, in the future, solve many genetic
birth defects such as downs syndrome. Somatic cell therapy deals with the direct
treatment of living tissues. Scientists, in a lab, inject the tissues with the
correct, functioning gene and then re-administer them to the patient, correcting
the problem (Clarke 1). Along with altering the cells of living tissues, genetic
engineering has also proven extremely helpful in the alteration of bacterial
genes. Transforming bacterial cells is easier than transforming the cells of
complex organisms (Stableford 34). Two reasons are evident for this ease of
manipulation: DNA enters, and functions easily in bacteria, and the transformed
bacteria cells can be easily selected out from the untransformed ones. Bacterial
bioengineering has many uses in our society, it can produce synthetic insulins,
a growth hormone for the treatment of dwarfism and interferons for treatment of
cancers and viral diseases (Stableford 34). Throughout the centuries disease has
plagued the world, forcing everyone to take part in a virtual lottery with the
agents of death (Stableford 59). Whether viral or bacterial in nature, such
disease are currently combated with the application of vaccines and antibiotics.
These treatments, however, contain many unsolved problems.
The difficulty with applying antibiotics to destroy bacteria is that natural
selection allows for the mutation of bacteria cells, sometimes resulting in
mutant bacterium which is resistant to a particular antibiotic. This
indestructible bacterial pestilence wages havoc on the human body. Genetic
engineering is conquering this medical dilemma by utilizing diseases that target
bacterial organisms. These diseases are viruses, named bacteriophages, which can
be produced to attack specific disease-causing bacteria (Stableford 61). Much
success has already been obtained by treating animals with a phage designed to
attack the E. coli bacteria (Stableford 60). Diseases caused by viruses are much
more difficult to control than those caused by bacteria. Viruses are not whole
organisms, as bacteria are, and reproduce by hijacking the mechanisms of other
cells. Therefore, any treatment designed to stop the virus itself, will also
stop the functioning of its host cell. A virus invades a host cell by piercing
it at a site called a receptor. Upon attachment, the virus injects its DNA into
the cell, coding it to reproduce more of the virus. After the virus is
replicated millions of times over, the cell bursts and the new viruses are
released to continue the cycle. The body's natural defense against such cell
invasion is to release certain proteins, called antigens, which plug up the
receptor sites on healthy cells. This causes the foreign virus to not have a
docking point on the cell. This process, however, is slow and not effective
against a new viral attack. Genetic engineering is improving the body's defenses
by creating pure antigens, or antibodies, in the lab for injection upon
infection with a viral disease.
This pure, concentrated antibody halts the symptoms of such a disease until
the bodies natural defenses catch up. Future procedures may alter the very DNA
of human cells, causing them to produce interferons. These interferons would
allow the cell to be able determine if a foreign body bonding with it is healthy
or a virus. In effect, every cell would be able to recognize every type of virus
and be immune to them all (Stableford 61). Current medical capabilities allow
for the transplant of human organs, and even mechanical portions of some, such
as the battery powered pacemaker. Current science can even re-apply fingers
after they have been cut off in accidents, or attach synthetic arms and legs to
allow patients to function normally in society.
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