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- 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.
-
- 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
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