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Paper 99
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THE POTENTIAL OF CRISPR TECHNOLOGY IN THE TREATMENT
OF DUCHENNE MUSCULAR DYSTROPHY
Aaron Mcvaugh, [email protected], Mahboobin, 4:00, Alexander Short, [email protected], Mahboobin, 4:00
Abstract— Duchenne muscular dystrophy (DMD) is an
inherited disease caused by mutations in gene encoding for
dystrophin, a protein that ensures muscle integrity. Without
this protein, one’s muscles will deteriorate with time. A new
genetic modification technique called CRISPR (Clustered
Regularly Interspaced Short Palindromic Repeat) could help
treat this disease. CRISPR works by altering the patient’s
DNA and replacing the mutated gene, allowing for the protein
to be produced in the body. CRISPR has an advantage over
other methods of treatment for DMD because of its accuracy,
simplicity, and cost, allowing for large scale production,
eventually.
The relevance of CRISPR technology on diseases such
as DMD is very significant to society as well as the field of
bioengineering. CRISPR therapy may allow people who
carry deleterious gene characteristics to have children
without passing on dangerous traits. There is a great
potential to improve the lives of people with degenerative
diseases, as well as to ensure the health of people in future
generations. Our paper will also expand on how this
developmental technology is interconnected with aspects of
sustainability.
Our paper will show the vast potential of CRISPR for a
large-scale impact on society.
We will express our
technology through many different examples and will use
various methods to explain CRISPR. One method is to utilize
the results of ongoing animal testing of this technology, as
well as information about the future of this technology on
human patients. These and many other sources will clearly
convey the importance of CRISPR.
Key Words— bioengineering, CRISPR, degenerative
diseases, gene encoding, genetic modification, Duchenne
muscular dystrophy, dystrophin
CRISPR TECHNOLOGY OFFERS NEW
TREATMENT FOR DUCHENNE
MUSCULAR DYSTROPHY
CRISPR technology is a revolutionary form of gene
editing. This new process has the potential to conquer a great
number of genetic disorders and can improve the lives of not
University of Pittsburgh, Swanson School of Engineering 1
Submission Date 31.03.2017
only current patients, but of those in future generations.
According to, What is Biotechnology.org, CRISPR/Cas9 is a
genetic engineering technology that can be used to identify
and edit the DNA of destructive viruses [1]. There are two
main components of this innovative technology. First, there
is the Cas9 system, which is “an enzyme that can cut a double
DNA strand at a very precise point, nick it, or block its gene
expression.” [1]. The second component is CRISPR, which
is a short strand of RNA used to guide the Cas9 enzyme to
bind with a genome sequence to make a cut [1]. Due to this
progression of events, scientists can disrupt the gene’s
function or insert a new sequence to code for a new function
[1]. This would allow scientists to identify a gene mutation
and then alter the mutation using this powerful system. The
CRISPR technology would cut the mutation from the DNA
and replace it with a healthy sequence. This ability to
virtually eliminate a genetic disorder is important in
developing new ways for doctors to increase the health of
their patients now and for generations to come. This new
process has very intriguing potential to scientists and
researchers, for use in healing people from diseases, but also
because it is an ethical and sustainable process.
This new technology can revolutionize gene editing and
have a positive impact on the lives of many people. One
specific area in which CRISPR can have a major influence is
with Duchenne Muscular Dystrophy. Per the Muscular
Dystrophy Association (MDA), “Duchenne muscular
dystrophy (DMD) is a genetic disorder characterized by
progressive muscle degeneration and weakness” [2]. DMD is
caused by the absence of the dystrophin protein that aids in
keeping muscle cells intact [2]. The lack of dystrophin causes
muscle cells to be weak and easily damaged [2]. In patients,
muscle weakness can begin as early as age three, first
affecting the muscles in the hips and pelvic area [2]. Later, it
affects the skeletal muscles in the arms and legs including an
enlargement of the calf muscles [2]. These symptoms have
major side effects on people’s lives and health. CRISPR has
the potential to help cure this disease, due to its unique ability
to edit genes. The system’s ability to cut and replace gene
mutations can play a key role in supplanting flawed
dystrophin genes in people with DMD. Even though the
future of this revolutionary technology shines brightly, it
currently cannot be used to cure DMD. This is because it is
Aaron Mcvaugh
Alexander Short
still in the laboratory test phase and is currently being tested
on mice and not humans. According to Science Magazine,
CRISPR could potentially be used in humans to cut out a
faulty exon so that the cell could then make a shortened
version of dystrophin [3]. This approach, while unperfected,
could play a major role in helping to cure DMD, as well as
open a new realm of possible solutions to battle other perilous
diseases.
for genome editing in eukaryotic cells [4]. The system
targeted and attacked the bad genome and removed it from the
cell. This astonishing method has been consistently effective
in simple life forms such as bacteria, as well as, more complex
life forms such as mice. This demonstrates its reliability and
effectiveness. Even from early testing, it is easy to see how
CRISPR has evolved into such a large area of interest in
human health care. This system has proven to be not only
dependable, but also powerful in its gene editing ability.
THE HISTORY OF CRISPR/CAS9 AND
GENETIC MODIFICATION
THE CRISPR/CAS9 MECHANISM
The CRISPR Mechanism in Viral Immune Response
Just like all major discoveries, the origin of the
CRISPR/Cas9 system has undergone much research over the
past twenty years. Per the Broad Institute, it was in 2005
when Francisco Mojica originally discovered CRISPR and its
function [4]. He identified that CRISPR was an adaptive
immune system for bacteria [4]. This means that bacteria
have the capability to identify and kill invaders to its system.
It is adaptive because it can remember previous attackers and
can use the same methods to destroy them yet again. This
important finding was critical in the development of CRISPR
as we know it today. It was also in 2005 that the second part
of the CRISPR system was discovered. Alexander Bolotin
discovered a large protein associated with CRISPR which was
designated as Cas9 [4]. He realized that Cas9 contained
spacers that were essential for target recognition and this
became known as protospacer adjacent motif (PAM) [4]. The
function of Cas9 as a targeting device in the current
technology stems from this discovery. This and many other
of the basic functions of this current day complex system were
identified within simple bacteria. In 2006, Eugene Koonin
discovered that CRISPR acts as the immune system within
bacteria that defends against phage DNA [4]. Koonin’s
discovery was an important follow-up to the discovery by
Mojica. Mojica previously identified that CRISPR defended
against some type of invasion and now Koonin realized that
phage DNA performed this invasion. These two discoveries,
in particular, were important in determining how CRISPR can
be functional in healing and protecting the DNA of species
such an animals or humans. Thus, spanning over a decade,
the basic functions of CRISPR have been deeply researched
and thoroughly understood. The design of the current
technology, and its ability to have an impact on other, more
complex life forms is derived from the immune system of
basic bacteria.
The original purpose of CRISPR in bacteria, was to
develop immunity from invading viral DNA. All cells,
human and bacteria alike, have DNA that code for proteins
which carry out many functions inside the cell. Viruses
essentially hijack the cell and force it to reproduce until the
host cell dies. Since all living organisms use similar DNA
structures, viruses can attack any cell in any organism,
including humans. These structures only differ slightly in
their composition. Per New England BioLabs, CRISPR
works as an adaptive immunity to viruses by remembering
viral DNA that was originally destroyed and thus easily
destroying the virus in the future [5]. This facet of CRISPR
is very important to its development in genetic modification.
There are three types of CRISPR immunity mechanisms,
although this paper will only focus on the second type due to
its importance in genetic modification. The mechanism for
CRISPR in bacteria is Cas1 and Cas2, which are variants of
the Cas9 protein [5]. They work to identify the viral DNA
and cut it into segments of about twenty base pairs [5]. In
order for the Cas proteins to identify the viral DNA, they must
use a short segment of base pairs of about three to five, called
a Protospacer Adjacent Motif (PAM) [5]. Per the US National
Library of Medicine, a PAM is required for Cas proteins to
cut at the segment of DNA [6]. This is a very important initial
step in the function of CRISPR. In order for the proper strand
of DNA to be cut it must be properly identified so that the
wrong strand of DNA is not attacked. This process of
properly and precisely identifying the bad location on a DNA
strand is very important to how this system functions. It also
highlights how well CRISPR can serve as a cure for genetic
disorders.
Along with crRNA, separate trans-activating crRNA
(tracrRNA) is also formed [5]. These two RNA sequences
from a duplex similar to the DNA double helix [6]. These
combinations are important to setting up the system so that it
can invade the organism and make the proper cuts. The
crRNA then works with Cas9 to destroy the invading DNA
[5]. These sequences of events are very specific, which is
important so that the system can attack and destroy the proper
strand of DNA. Thus, the mechanism must be split up into
parts so that it can work seamlessly and cut the invading viral
Translation of Early Research to the Functionality of
CRISPR/Cas9
The discoveries regarding simple bacteria in the early
twenty-first century were very important to the development
of CRISPR. They essentially describe the basic functionality
of how CRISPR is used now. In 2013, Feng Zheng and his
team were the first people to successfully use CRISPR/Cas9
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DNA. This next section will describe the usefulness of this
biological process in terms of genetic modification.
mutations in the gene for dystrophin resulting in muscle
degradation. Since the cause is the lack of dystrophin in the
patient’s body, this disorder is a good candidate for genetic
modification to signal the DNA cells to produce more
dystrophin. DMD has been cured in lab mice, as well as,
isolated human cells. In a study regarding DMD in mice,
embryos of mdx (dystrophin deficient) mice were modified
with CRISPR/Cas9 [8]. According to the academic journal,
Science, mdx mice are good models to utilize for replicating
human disease and have a mutation in their gene regarding in
a lack of dystrophin [8]. In this study, the mice had a
nonsense mutation in exon 23 in the gene for dystrophin [8].
Thus, these mice all had significant protein deficiencies. A
nonsense mutation is a mutation that codes for a premature
stop codon, ending the protein synthesis before a function
protein is completed [8]. This means that the mice do not
have the ability to produce dystrophin because the stop codon
halts the process. This represented a genetic problem in the
mice that needed to be repaired using CRISPR technology.
Groups of both normal and mdx mice were injected with
elements of CRISPR [8]. There were also two control groups
for both the normal and mdx mice that were not injected [8].
Restriction fragment length polymorphisms (RFLP) were
used to identify the corrected gene in the mdx mice [8]. A
RFLP is a useful tool in comparing two different sets of DNA,
in this case the control and modified groups, which shows if
the correction was successful [8]. The resulting mdx mice
showed a mix of corrected and uncorrected cells [8]. Analysis
of hind limb muscle, respiratory muscle, and heart muscle was
performed on both normal, and mdx corrected mice which
were all at seven to nine years of age [8]. The analysis showed
some of the mdx mice had a complete absence of the typical
signs of DMD in the mdx mice [8]. This means that the
CRISPR system correctly removed the dangerous DNA and
implemented a healthy sequence. This healthy sequence then
effectively contributed to the production of dystrophin which
allows for proper muscle functioning and growth.
This result is a very positive sign. It proves that CRISPR
can be applied to more complex organisms than just bacteria.
The results of this testing show that CRISPR is effective in
repairing the damaged muscles caused by the effects of DMD.
This was shown by conducting muscle performance testing.
In the testing, the cured mdx mice exhibited enhanced muscle
performance compared to the uncured mdx mice [8]. Thus,
the system had positive effects, not only in the DNA coding,
but also in the terrible ramifications of this disorder. This
finding is important to the widespread use of this technology.
The vast capability of this system in genetic modification has
hope for great success in human patients.
The CRISPR Mechanism Compared to Other Methods
The CRISPR system is not without limitations;
however, it still compares favorably to other genetic
modification techniques. For example, retargeting Cas9 is
simple to do, since only twenty base pairs of crRNA need to
be changed [7]. Other methods of genetic modification are
TALEN and zinc fingers (ZNF). ZNFs are composed of many
zinc ‘fingers’ that can target three to four base pairs and
combining them allow it to target a specific area. However,
ZNFs are expensive and time consuming to produce.
TALENs are built from amino acid arrays which target a
single nucleotide and can be arranged to target the gene.
While TALENs are easier to produce and cheaper then ZNFs,
both do not compare as favorably to CRISPR [7]. Unlike
TALENs and ZNFs, CRISPR is not man made and is
relatively simple which makes it much easier and cheaper to
produce. Thus, the simplistic nature of CRISPR allows it to
be more effective during the process of targeting, cutting, and
replacing the genes. Another favorable aspect of CRISPR is
that Cas9 cuts specifically between two base pairs while
TALENs cleaves anywhere in a range of twelve base pairs [7].
This is very vital because imprecisely cutting the DNA can
lead to off target mutations which can be detrimental to the
health of the patient receiving treatment
However, an important characteristic of all genetic
modification techniques is that they all make positive
mutations as well as off target mutations. The percentage of
desired mutations achieved compares favorably for CRISPR
in relation to TALENs and zinc fingers. CRISPR has
achieved percentages of about 70% while TALENs and zinc
fingers range between 1% and 50% [5]. This means that
CRISPR makes a higher percentage of positive genetic
mutations that can benefit the patient versus other methods.
TALENS and zinc fingers result in some positive mutations,
but also in more harmful genetic mutations compared to
CRISPR. Off target mutations usually occur in regions where
there are only a few base pair differences between it and the
target region. Cas9 can tolerate up to five base pair
differences [5]. This means that it can tolerate these
differences without causing off target mutations. Thus,
research has shown that CRISPR has the capability to provide
a safer and easier method of performing genetic modification.
This is important to the health of patients who need reliable
technology that can cure debilitating disorders.
THE ROLE OF CRISPR/CAS9 IN CURING
DMD
Currently, CRISPR is unable to cure human patients
with DMD; however, ongoing achievements in this
technology give a hopeful outlook. DMD is caused by
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processes are still being studied to minimize the potential of
mutations in both the TALENs and CRISPR system.
In general, the results of the comparison test proved
there is no major overall difference in the effectiveness
between TALENs and CRISPR. However, it was found that
in using iPSCs pathways, the TALENs approach is not as
reliable as using CRISPR, specifically in targeting DNA
without having a large number of genetic mutations. This is
an important characteristic of CRISPR that sets it apart from
other gene modifying approaches. CRISPR proves to be more
effective because it does not require as many genetic
mutations. This is critical because the fewer genetic
mutations that occur, the less likely the patient is harmed. The
results of this study serve as a pathway to more complicated
testing within the human body.
The next step in this process would be to transplant the
corrected iPSCs cells back into the patient [9]. From there,
the iPSCs cells could merge with myofibers or, more
efficiently, correct surrounding cells that will aid the
myofibers [9].
Even though testing these methods in human cells is
promising, there are currently a few problems that researchers
most resolve. The faults lie in both the exon skipping and
frameshift methods. For these methods to be considered
successful, the US National Library of Medicine notes that the
number of corrected genes would need to be great, since 30%
to 40% of body weight is being affected [10]. This is very
important to scientists because they cannot move on to human
trials if the results are not significant enough to have a major
effect on the body.
In conclusion, this comparative study found that the
genetic modification method of TALENs is not as effective as
using CRISPR directly. Although this testing proves that
CRISPR can be utilized in different situations to work with
genetic modification, there are many more humanized tests
that need to be performed.
Dystrophin Gene Correction in iPSCs Derived from
Human Cells
FIGURE 1[9]
Corrected and uncorrected myofibers
Currently, experiments for human DMD correction are
limited to lab conditions outside of the human body. One such
laboratory experiment compared the usefulness of CRISPR in
curing DMD to other methods of genetic modification. One
specific method of comparison relates the TALENs system to
CRISPR. TALENs, as discussed earlier, is another method of
genetic modification that has been found to be similarly
favorable in modifying defective genes, but is not always
perfect in gene repair. Due to the process of developing these
technologies, experiments for human DMD correction are
limited to lab conditions outside of the human body. One
study, comparing these two technologies, describes multiple
correction pathways for curing DMD in patient-derived
induced pluripotent stem cells (iPSCs), which are stem cells
derived from adult cells. Per Science Direct, this study uses
cells from a DMD patient with a deletion of a DNA coding
region converted into iPSCs [9]. The results of the process
can be seen in Figure 1 where the dystrophin gene is produced
through by the combination of different steps, including, exon
skipping, frameshifting and genome editing. These three
steps are used to complete gene editing in both the CRISPR,
as well as the TALENs technology.
Studying both
technologies by the same set of methods, allows the
researchers gather information more effectively to compare
TALENs versus CRISPR.
This comparison test begins with insertion or deletion
mutations, called indel mutations, cause the reading frame to
shift, disrupting not only the immediate area of the mutation,
but the rest of the gene sequence [9]. Exon skipping works to
restore the reading frame, resulting in a dystrophin protein
that is partially functional [9]. The next step, frameshifting,
attempts to restore the reading frame by making more indel
mutations and shifting the frame further [9]. Finally, the
system is ready to perform gene editing procedures. Although
these steps can produce positive results, the fact of having
mutations is not always a promising sign. However, these
CRISPR in the Future: Challenges to Overcome
The largest concern regarding CRISPR and other
genetic modification technologies is the chance of off target
mutations to the genome. As previously stated, Cas9 will
tolerate differences up to five base pairs in the crRNA and
will not tolerate any differences in the PAM sequence. The
zero tolerance in the PAM sequence is limiting, but necessary.
Thus, any use of CRISPR must also analyze potential sites for
off target mutations. Even then, some areas might contain so
many high potential sites that CRISPR would be ineffective.
In addition, iPS cell transplantation after correction still has
not been fully developed and embryo correction is also not
currently possible. CRISPR is a promising tool and its
development will undoubtedly open new doors for treatment
for DMD and beyond. However, no single tool or method has
been proven to be perfect and thus each treatment must be
specifically tailored to ensure safe and positive outcomes.
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health of future generations. This technology can allow for
children to grow, free of disorders that they would normally
contract from their parents. Thus, the ability of this procedure
would be life saving for many families and individuals.
However, there is simply not enough justification of the
CRISPR technology to allow for its use in genome editing at
its current state. There is great hope that this technology can
be a bridge to a new age of treating patients with not only
muscular dystrophy but with other degenerative diseases.
Yet, there are too many ethical concerns for this system to be
put into clinical use. It is not yet proven that CRISPR will not
attack the wrong DNA strand or cause other genetic
mutations. Thus, because of the lack of evidence to prove
otherwise, the rule and codes of ethics overpower the benefits
of this unique technology, at this time.
ETHICAL CONSDERATIONS OF CRISPR
TECHNOLOGY
The great potential for this technology is exciting to both
researchers and scientists. However, since this technology is
still in the research stage of development, scientists and
bioengineers must discuss other factors as well. Scientists
must consider the different impacts CRISPR would have on
society if/when it became introduced into the market. Per the
Journal of Clinical Research and Bioethics, “An important
ethical issue in research is that benefits must be greater than
risks. Greater attention must be placed on risks, since they
may damage living beings or the environment.” [11]. These
are two very important pieces of information, because even
though CRISPR has great positive potential as a technology,
we must find a balance between the benefits and the risks.
One concern is that large genomes may contain identical or
homologous DNA sequences to the targeted harmful DNA.
[11]. CRISPR/Cas9 may split the unintended DNA sequences
causing mutations and even cell death [4]. Due to this,
improvements have been made to reduce off target mutations
as scientists try to ensure that the benefits of CRISPR greatly
outweigh its risks.
Another source of ethical consideration is in the
possibility of genome editing in human germline [11]. This
is the genome that can be passed on to future generations by
gametes (fertilized eggs) [11]. There is concern that the
CRISPR/Cas9 system can produce mutations and side effects
that may transmit to future generations [11]. This is
concerning to researchers because at the current time, they are
unsure if there would be side effects that would cause harm to
offspring. This alarm also goes hand-in-hand with the
inability of unborn children to give consent on such matters.
Great care and thought should be taken because these risks
could potentially affect their lives [4]. Currently, the risks of
these side effects greatly outweigh the potential benefits,
causing this method of CRISPR to be postponed until further
studies can prove otherwise. In order for this technique to be
ethically safe for future generations, scientists need to develop
the system with little to no potential side effects of mutations.
Even though there are still serious concerns regarding
germline genome editing, very invaluable aspects to using
CRISPR in germlines exist. According to BioMed Central,
CRISPR can be used to improve the human condition of
offspring and future generations through the eradication of
deleterious mutations [12]. The article states, “It might allow
people who carry such deleterious traits to have children to
whom they are genetically related without the prospect of
passing on problematic or dangerous conditions. To the
extent these changes would persist across the generations, it
could benefit not only the immediate offspring, but also all of
the descendants of those who use the technology.” [12]. This
potential benefit is groundbreaking in the field of health and
medicine. CRISPR has the capability to affect the wellbeing
of not only people of the current age, but also to protect the
Sustainability and CRISPR
CRISPR not only has many different ethical
considerations, but it also has an important foothold in the
field of sustainability. UCLA says, “sustainable development
is development that meets the needs of the present without
compromising the ability of future generations to meet their
own needs” [13]. This definition relates to CRISPR because
the entire basis of the technology is working to meet the needs
of current day people. Presently, there are not many
treatments for genetic disorders, such as DMD, that are
effective. Some of the available treatments also hold the risk
of causing off target mutations in a patient’s genome.
CRISPR technology is a system that can be proven to meet
the needs of people without harming their livelihood.
CRISPR can also be utilized to enhance the livelihood of
future generations, as well.
CRISPR is being studied to provide a safer and more
effective technique to dispose of harmful DNA in the genome.
Based on tests, CRISPR has been more effective in restoring
the dystrophin gene to end the effects of DMD than other
methods such as TALENs and zinc fingers. Not only is
CRISPR more beneficial, but it also comes with less chance
of producing genetic mutations. This clarifies the effect
CRISPR has on sustainability. This technology is being
designed with the current needs of people in mind and it has
the potential to service these needs with little chance of harm.
It also does not compromise the needs of the future because a
possible function of its design is to eliminate the traits of
genetic diseases in offspring so that they do not carry on their
parents’ genetic disorder. This technology was designed with
not only short term goals in mind, but is also geared toward
the future and the positive effect it can have on generations to
come.
Thwink.org defines sustainability in a different manner.
It states that sustainability is “the ability to continue a defined
behavior indefinitely” [14]. This definition brings up a
different spin on sustainability than the previous one. The
concept behind this definition is that if something is
sustainable it is kept in a similar form or state for a long period
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of time. CRISPR technology meets this definition of
sustainability because it preserves the quality of life,
indefinitely once it is utilized. Genetic disorders can
significantly disrupt the health of the individuals. CRISPR
has the potential to cure genetic disorders through genetic
modification and can eliminate the harmful effects of these
terrible diseases. Many people are in need of better healthcare
technology and more efficient methods to improve their
overall health. The functionality of CRISPR provides a
cornerstone for better technology that can improve the overall
wellbeing of many patients immediately and then sustain that
health over the long term. CRISPR can help to improve the
health of people in the present, while also protecting offspring
of the future. This dual nature of this revolutionary system
clearly shows how it fits perfectly into the concept of
sustainability. Sustainability evolves around improving the
overall condition of life, in the present state and sustaining
that improved condition, while not compromising the state of
health of future generations. CRISPR can transform the
world of genetic modification, improving lives in the current
state, maintaining this improved state of health, and
improving the health of future generations.
The concept and study of sustainability is very important
to the work and efforts of all engineers. The design of
CRISPR and its many abilities serve as a perfect mixture of
meeting current needs while not compromising future needs.
Its capabilities are unique and are fitted to prove long
sustainability for the health of current and future patients.
Therefore, CRISPR plays an essential role in sustaining
quality of life.
discovery. The purpose of CRISPR to help cure DMD in
humans follows the same basic steps as it would in protecting
bacteria. This technology has been proven, not only in a lab,
but in nature, by protecting a very simple version of life,
bacteria.
The CRISPR/Cas9 system is very complex and it
involves many different types of systems and tools to perform
various functions inside a bacterium. However, the most
important function for humans is the potential to remove bad
DNA. To do so, CRISPR follows a series of important steps
that are crucial to its ability to perform genetic modification.
CRISPR can easily be delivered to an organism’s system. Its
main components include crRNA, tracRNA, Cas9, and a
repair template for DNA. These components are essential to
the specific functions of this technology. They are involved
in targeting the harmful DNA so that the Cas9 protein can
dissect the DNA.
This dissection is where healthy,
replacement DNA can be transferred. This method of
repairing DNA sequences is specific to its purpose, as well as
revolutionary in the field of biomedicine. This process also
has an upper hand over the less reliable methods that can be
related to producing a fair amount of genetic mutations. Thus,
this system is on the verge of innovative medical technology
that can outperform older and more inaccurate methods.
One of the biggest potential uses of this technology is in
the form of curing DMD. Even though this apparatus is in the
early stages of development, it shows positive signs or a
hopeful outlook. Tests on mice have shown that the
possibility of using CRISPR on human organisms to cure
DMD is not far into the future. When tested on mice almost
half off the alleles that were corrected by the CRISPR process
had no signs of DMD. Even though this value may seem low,
it is a very positive sign for a technology that is in the early
stages of development. This advancement gives way for
CRISPR having the potential to cure more complex
multicellular organisms, such as humans.
This technology has the capability to save people’s lives
in many different fashions. However, one very important
possibility is curing DMD which is a debilitating and
treacherous disorder. Early success in development, as well
as the long history of CRISPR, has shown glimpses of this
technology’s potential. Even though there are ethical
concerns, they are only prominent because of the preliminary
stages of this system. When looking past these concerns, the
road ahead for CRISPR is a very promising one. Even with
many more trials and tests along the way, there is a light at the
end of the tunnel for a truly inspirational and exhilarating
technology.
CRISPR HAS THE POTENTIAL TO BE A
BREAKTHROUGH TECHNOLOGY
Even though CRISPR technology is still in clinical
stages, it is very evident that this system has bright hope for a
very prominent future. The potential to virtually wipe out
medical disorders and diseases such as Duchenne Muscular
Dystrophy (DMD) is very appealing to scientists in the field
of medicine. CRISPR would virtually remove damaging
DNA and replace it with a healthy strand. The combination
of using the functions of CRISPR, as well as the Cas9 system
provide a powerful one-two punch to knock out even the
worst genetic disorders, such as DMD. This approach can
save lives of not only current patients, but also has the
possibility to work in the human germline to help prevent this
disease from being passed on to offspring. A system that can
perform genetic-type healing has great value in the field of
medicine and bioengineering.
This technology’s budding future stems from the origins
of its history. Scientists over the past years have worked to
perfect and improve this system in hopes of progressing it out
of clinical trials. As more research has been completed, the
capability of this technology has increased. However, the
basic functionality of CRSIPR can be traced back to its early
SOURCES
[1] “What is Biotechnology?” The Biotechnology and
Medicine Education Trust. 2016. Accessed 2.24.2017.
http://www.whatisbiotechnology.org/science/crispr
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Aaron Mcvaugh
Alexander Short
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ACKNOWLEDGEMENTS
We would like to thank our writing instructor Professor
Zellmann for guiding us throughout this writing process. We
would also like to thank our session co-chair Mikayla
Ferchaw for her continued advice and support. Her
knowledge about this assignment is very important to our
success and she has been a great help. We are very grateful
for their support during this paper and we are thankful for
their aid in creating the final portion of this paper.
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