Genetic Engineering, History And Future: Altering The Face Of Science Essay, Research Paper
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 anoth
erstrand 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 supplyof
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
treatmen ts, 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.
Works Cited
Clarke, Bryan C. Genetic Engineering. Microsoft (R) Encarta. Microsoft
Corporation, Funk & Wagnalls Corporation, 1994.
Davis, Bernard, and Lissa 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