Genetic Engineering (2805 words)

Genetic Engineering
Genetic Engineering, history and future Altering the Face of Science Science is
a creature that continues to evolve at a much higher rate than the beings that
gave it birth. The transformation time from tree-shrew, to ape, to human far
exceeds the time from analytical engine, to calculator, to computer. But
science, in the past, has always remained distant. It has allowed for advances
in production, transportation, and even entertainment, but never in history will
science be able to so deeply affect our lives as genetic engineering will
undoubtedly do. With the birth of this new technology, scientific extremists and
anti-technologists have risen in arms to block its budding future. Spreading
fear by misinterpretation of facts, they promote their hidden agendas in the
halls of the United States congress. Genetic engineering is a safe and powerful
tool that will yield unprecedented results, specifically in the field of
medicine. It will usher in a world where gene defects, bacterial disease, and
even aging are a thing of the past. By understanding genetic engineering and its
history, discovering its possibilities, and answering the moral and safety
questions it brings forth, the blanket of fear covering this remarkable
technical miracle can be lifted. The first step to understanding genetic
engineering, and embracing its possibilities for society, is to obtain a rough
knowledge base of its history and method. The basis for altering the
evolutionary process is dependant on the understanding of how individuals pass
on characteristics to their offspring. Genetics achieved its first foothold on
the secrets of nature’s evolutionary process when an Austrian monk named Gregor
Mendel developed the first “laws of heredity.” Using these laws,
scientists studied the characteristics of organisms for most of the next one
hundred years following Mendel’s discovery. These early studies concluded that
each organism has two sets of character determinants, or genes (Stableford 16).

For instance, in regards to eye color, a child could receive one set of genes
from his father that were encoded one blue, and the other brown. The same child
could also receive two brown genes from his mother. The conclusion for this
inheritance would be the child has a three in four chance of having brown eyes,
and a one in three chance of having blue eyes (Stableford 16). Genes are
transmitted through chromosomes which reside in the nucleus of every living
organism’s cells. Each chromosome is made up of fine strands of deoxyribonucleic
acids, or DNA. The information carried on the DNA determines the cells function
within the organism. Sex cells are the only cells that contain a complete DNA
map of the organism, therefore, “the structure of a DNA molecule or
combination of DNA molecules determines the shape, form, and function of the
[organism’s] offspring ” (Lewin 1). DNA discovery is attributed to the
research of three scientists, Francis Crick, Maurice Wilkins, and James Dewey
Watson in 1951. They were all later accredited with the Nobel Price in
physiology and medicine in 1962 (Lewin 1). “The new science of genetic
engineering aims to take a dramatic short cut in the slow process of
evolution” (Stableford 25). In essence, scientists aim to remove one gene
from an organism’s DNA, and place it into the DNA of another organism. This
would create a new DNA strand, full of new encoded instructions; a strand that
would have taken Mother Nature millions of years of natural selection to
develop. Isolating and removing a desired gene from a DNA strand involves many
different tools. DNA can be broken up by exposing it to ultra-high-frequency
sound waves, but this is an extremely inaccurate way of isolating a desirable
DNA section (Stableford 26). A more accurate way of DNA splicing is the use of
“restriction enzymes, which are produced by various species of
bacteria” (Clarke 1). The restriction enzymes cut the DNA strand at a
particular location called a nucleotide base, which makes up a DNA molecule. Now
that the desired portion of the DNA is cut out, it can be joined to another
strand of DNA by using enzymes called ligases. The final important step in the
creation of a new DNA strand is giving it the ability to self-replicate. This
can be accomplished by using special pieces of DNA, called vectors, that permit
the generation of multiple copies of a total DNA strand and fusing it to the
newly created DNA structure. Another newly developed method, called polymerase
chain reaction, allows for faster replication of DNA strands and does not
require the use of vectors (Clarke 1). The possibilities of genetic engineering
are endless. Once the power to control the instructions, given to a single cell,
are mastered anything can be accomplished. For example, insulin can be created
and grown in large quantities by using an inexpensive gene manipulation method
of growing a certain bacteria. This supply of insulin is also not dependant on
the supply of pancreatic tissue from animals. Recombinant factor VIII, the blood
clotting agent missing in people suffering from hemophilia, can also be created
by genetic engineering. Virtually all people who were treated with factor VIII
before 1985 acquired HIV, and later AIDS. Being completely pure, the
bioengineered version of factor VIII eliminates any possibility of viral
infection. Other uses of genetic engineering include creating disease resistant
crops, formulating milk from cows already containing pharmaceutical compounds,
generating vaccines, and altering livestock traits (Clarke 1). 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, however, 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 now 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. But would not it be incredibly convenient if the human body could
simply regrow what it needed, such as a new kidney or arm? Genetic engineering
can make this a reality. Currently in the world, a single plant cell can
differentiate into all the components of an original, complex organism. Certain
types of salamanders can re-grow lost limbs, and some lizards can shed their
tails when attacked and later grow them again. Evidence of regeneration is all
around and the science of genetic engineering is slowly mastering its
techniques. Regeneration in mammals is essentially a kind of “controlled
cancer”, called a blastema. The cancer is deliberately formed at the
regeneration site and then converted into a structure of functional tissues. But
before controlling the blastema is possible, “a detailed knowledge of the
switching process by means of which the genes in the cell nucleus are
selectively activated and deactivated” is needed (Stableford 90). To obtain
proof that such a procedure is possible one only needs to examine an early
embryo and realize that it knows whether to turn itself into an ostrich or a
human. After learning the procedure to control and activate such regeneration,
genetic engineering will be able to conquer such ailments as Parkinson’s,
Alzheimer’s, and other crippling diseases without grafting in new tissues. The
broader scope of this technique would allow the re-growth of lost limbs,
repairing any damaged organs internally, and the production of spare organs by
growing them externally (Stableford 90). Ever since biblical times the lifespan
of a human being has been pegged at roughly 70 years. But is this number truly
finite? In order to uncover the answer, knowledge of the process of aging is
needed. A common conception is that the human body contains an internal
biological clock which continues to tick for about 70 years, then stops. An
alternate “watch” analogy could be that the human body contains a
certain type of alarm clock, and after so many years, the alarm sounds and
deterioration beings. With that frame of thinking, the human body does not begin
to age until a particular switch is tripped. In essence, stopping this process
would simply involve a means of never allowing the switch to be tripped. W.

Donner Denckla, of the Roche Institute of Molecular Biology, proposes the alarm
clock theory is true. He provides evidence for this statement by examining the
similarities between normal aging and the symptoms of a hormonal deficiency
disease associated with the thyroid gland. Denckla proposes that as we get older
the pituitary gland begins to produce a hormone which blocks the actions of the
thyroid hormone, thus causing the body to age and eventually die. If Denckla’s
theory is correct, conquering aging would simply be a process of altering the
pituitary’s DNA so it would never be allowed to release the aging hormone. In
the years to come, genetic engineering may finally defeat the most unbeatable
enemy in the world, time (Stableford 94). The morale and safety questions
surrounding genetic engineering currently cause this new science to be cast in a
false light. Anti-technologists and political extremists spread false
interpretation of facts coupled with statements that genetic engineering is not
natural and defies the natural order of things. The morale question of
biotechnology can be answered by studying where the evolution of man is, and
where it is leading our society. The safety question can be answered by
examining current safety precautions in industry, and past safety records of
many bioengineering projects already in place. The evolution of man can be
broken up into three basic stages. The first, lasting millions of years, slowly
shaped human nature from Homo erectus to Home sapiens. Natural selection
provided the means for countless random mutations resulting in the appearance of
such human characteristics as hands and feet. The second stage, after the full
development of the human body and mind, saw humans moving from wild foragers to
an agriculture based society. Natural selection received a helping hand as man
took advantage of random mutations in nature and bred more productive species of
plants and animals. The most bountiful wheats were collected and re-planted, and
the fastest horses were bred with equally faster horses. Even in our recent
history the strongest black male slaves were mated with the hardest working
female slaves. The third stage, still developing today, will not require the
chance acquisition of super-mutations in nature. Man will be able to create such
super-species without the strict limitations imposed by natural selection. By
examining the natural slope of this evolution, the third stage is a natural and
inevitable plateau that man will achieve (Stableford 8). This omniscient control
of our world may seem completely foreign, but the thought of the Egyptians
erecting vast pyramids would have seem strange to Homo erectus as well. Many
claim genetic engineering will cause unseen disasters spiraling our world into
chaotic darkness. However, few realize that many safety nets regarding
bioengineering are already in effect. The Recombinant DNA Advisory Committee (RAC)
was formed under the National Institute of Health to provide guidelines for
research on engineered bacteria for industrial use. The RAC has also set very
restrictive guidelines requiring Federal approval if research involves
pathogenicity (the rare ability of a microbe to cause disease) (Davis, Roche
69). “It is well established that most natural bacteria do not cause
disease. After many years of experimentation, microbiologists have demonstrated
that they can engineer bacteria that are just as safe as their natural
counterparts” (Davis, Rouche 70). In fact the RAC reports that “there
has not been a single case of illness or harm caused by recombinant [engineered]
bacteria, and they now are used safely in high school experiments” (Davis,
Rouche 69). Scientists have also devised other methods of preventing bacteria
from escaping their labs, such as modifying the bacteria so that it will die if
it is removed from the laboratory environment. This creates a shield of complete
safety for the outside world. It is also thought that if such bacteria were to
escape it would act like smallpox or anthrax and ravage the land. However,
laboratory-created organisms are not as competitive as pathogens. Davis and
Roche sum it up in extremely laymen’s terms, “no matter how much Frostban
you dump on a field, it’s not going to spread” (70). In fact Frostbran,
developed by Steven Lindow at the University of California, Berkeley, was
sprayed on a test field in 1987 and was proven by a RAC committee to be
completely harmless (Thompson 104). Fear of the unknown has slowed the progress
of many scientific discoveries in the past. The thought of man flying or
stepping on the moon did not come easy to the average citizens of the world. But
the fact remains, they were accepted and are now an everyday occurrence in our
lives. Genetic engineering too is in its period of fear and misunderstanding,
but like every great discovery in history, it will enjoy its time of realization
and come into full use in society. The world is on the brink of the most
exciting step into human evolution ever, and through knowledge and exploration,
should welcome it and its possibilities with open arms
Bibliography
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Roche. “Sorcerer’s Apprentice or Handmaiden to Humanity.” USA TODAY:
The Magazine of the American Scene [GUSA] 118 Nov 1989: 68-70. Lewin, Seymour Z.

Nucleic Acids. Microsoft (R) Encarta. Microsoft Corporation, Funk ; Wagnalls
Corporation, 1994. Stableford, Brian. Future Man. New York: Crown Publishers,
Inc., 1984. Thompson, Dick. “The Most Hated Man in Science.” Time 23
Dec 4 1989: 102-104