Gene Doping: An Untamed Threat - La Sierra University

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Dec 12, 2012 (5 years and 25 days ago)

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Running Head: GENE DOPING: AN UNTAMED THREAT

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Gene Doping: An Untamed Threat

Aaron Snyder

La Sierra University













GENE DOPING: AN UNTAMED THREAT


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In the last twenty years

an arms race against the possible threat of gene doping. The
World Anti
-
Doping Agency (WADA) has spent countless hours
funding, gathering, developing
and analyzing research
to find the answer key to the ultimate test. While scientists
claim

gene
doping is a reality no one kn
ows for certain. It is

the world’s best
-
kept secret. This research
paper will discuss what gene dopi
ng is, the
history of

gene therapy, the concept of application,
problems with

gene doping usage
, and the implications for the future of the Olympic games.


In the last few years,

the World Anti
-
Doping Agency

[WADA]
has altered the definition
of ‘gene dopi
ng’.

In 2009, “The

Prohibited List


defined gene doping as,


The transfer of cells or
genetic elements or the use of cells, genetic elements or pharmacological agents to modulating
expression of endogenous genes having the capacity to enhance athletic perf
ormance […]” This
definition was later simplified
in “The 2012 Prohibited List”
for the 2012
Olympic
games as,

The following, with the potential to enhance sport performance, are prohibited:
t
he transfer of
nucleic acids or nucleic acid sequences;
t
he use

of normal or genetically modi
fied cells


(WADA, 2012).

In

laymen’s terms
,

gene doping is the
modification and enhancement of genes
to improve human athletic performance.
This is mainly used i
n the process of trying to
create

a
genetically modified athlete

there are many platforms for modification.


The present platforms consist of viral and non
-
viral vectors.
Viral

vectors, as

means of
modification
s

of DNA
,

are used to transport modified DNA to new cells to be reinserted as new
DNA
.
The new cell then
replicates this DNA and incorporates it

into

the master DNA
,

ready
to
be used to make new enhanced proteins
.
For example, a
s the master DNA is replicated it code
s

for
muscle enhancing proteins
specific

to the
athletic ability it was designed for
.
Some of t
he
common viral vectors include: adenovirus, adeno
-
associated virus (AAV), herpesvirus,
GENE DOPING: AN UNTAMED THREAT


3

oncoretrovirus, and lentivirus.
Unlike the use of non
-
viral vectors, t
he
uses of viral vectors, in
theory, are

prime vectors for transport; however, they are associated

with
a number of

fatal
problems.


The major problems associated with the use of viral platforms are that they are
completely uncontrollable.
Viruses or “retroviruses”
can

cause immune responses from the body,
and usually

the DNA
does not

m
ake it to the
appropriate cells;

if they did they turned off with
time (Potter, 2010
, p.

166
). The b
ody
,

unfortunately
,

still responds

to the fact that the vessel
carrying
the
new DNA is a foreign
cell, which

causes the immune system to respond
by

try
ing

to
kill the ret
rovirus. Sometimes the viruses
will

insert
their

DNA into an unwanted cell
possibly
causing

some harmful effects.
According to biologist
, Dr. Reiss and
moral philosopher
Dr.
Straughan (1996)
, “In addition to
there

random insertion, retroviruses are quite d
ifficult to
control. Potential consequences may entail merely a lack of effectiveness, or, more seriously,
insertion into tumour
-
supressor genes, which help prevent cancer” (
as cited in Miah, 2004, p.45
).
The fact that the viruses can cause cancer is an al
arming issue
. Gene doping

should be
well
contemplated

before
experimenting

with

them

as means of modifying one’s DNA to become a
better athlete.
The
problem can be avoided

with
the use of non
-
viral platforms.


The use of non
-
viral vectors will allow the
body to be more accep
ting of new DNA.
Professor
DJ Wells
, Department of Cellular and Molecular Neuroscience at Imperial London
College,

author of


Gene doping: the hype and the reality


states, “Such immune responses can
be avoided by the use of a syntheti
c non
-
viral vector. In the simplest form there is just a circular
fo
rm of DNA, known as plasmid DNA” (2008
, p. 625
).
This form of DNA would have to be
administered by a muscular injection into a specific site on the muscle. Plasmid DNA is seen as
less prod
uctive than viral vectors, but they have the potential to be more effective when
coupled
GENE DOPING: AN UNTAMED THREAT


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with a form of activation.

For instance, i
t is

the same concept as

like pushing a ball
from the top
of a ramp
with
just hard enough

force

to
get

it moving before gravi
ty takes
over
as the ball
propels

down the

hil
l. I
t
is
very similar to
th
e concept of activation energy
.
Scientists will use
enzymes as activators to lower the activation energy of a reaction to make it react quicker than if
it were in its natural state.
The process as it pertains to plasmid DNA delivery is called
electroporation.

Electroporation involves subjecting a solution of genetically engineered cells and foreign
DNA with a sudden high
-
voltage electrical field, which stimulates the integration of t
he new
genetic material into the host cells (
Miah, 2004
, p. 45
).

In essence it is like the birth of
Frankenstein. The mad scientist needs a jolt of electricity to finally get his creation to come alive.
The same concept applies with the use of plasmid DNA
because t
he investigator must jolt
,

or add
a physical enhancement to the plasmids in order to induce integration of the new DNA and the
foreign DNA.
According to
professors Aihara and Miyazaki
(1998)
from the
department of
Nutrition and Physiological Chemi
stry at Osaka University Medical School
,
Llouis M. Mir
et al.
(1999)
from the National Center of Scientific Research of France,
and J.M. McMahon

et al.
(2001)

from the departmen
t of Medicine of Austin Health
,

The application of a series of
electrical
pulses following intramuscular injection (in vivo electroporation) can increase the
efficiency of plasmid DNA delivery over 1
,
000
-
fold

and geneti
cally modify the majority
of the
target muscle fibers
” (
as cited in Wells,
2008
, p. 625
).

Wells

suggests

that
t
he process of
electroporation in
tegration of plasmid DNA is safer and more

efficient than the use of a virus
vector
because of

the problems of randomized cell integration, which could lead to cancer
,

as
explained previously.
There are
also
other
alternativ
e methods

of gene expression that can be
used to help build muscle.

GENE DOPING: AN UNTAMED THREAT


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The
uses of specific proteins and processes have
shown

the

benefits
of

increase
d

muscular strength and impr
ove
d

performance. They are
termed
insulin like growth factor 1 (IGF
-
1)
, myostatin,
erythropoietin

(Epo)
, and perioxisome
-
proliferator activator receptor

(P
P
RA
)
.

IGF
-
1 is a protein that codes for increases in muscular
hypertrophy

and
decreased

atrophy due to aging
.
It is a protein that
acts

like
the
insulin
that
is produced
in the human
. Andy
Miah
,

author of
Genetically Modified Athletes
,

quotes medical physiologist Dr. Barton
-
Davis
et
al.
(1998) and kinesiologist Dr. Lee
et al.
(2004) in

his research, “[…] Lee Sween
e
y has
researched the possibilities for using a synthetic form of IGF
-
1 to repair muscle tissue, which has
demonstrated considerable enhancements in its application to mice
(
as cited in
Miah, 2010
, p.
48
)
.
IGF
-
1 definitely has been shown to improve muscul
ar

strength by amazing numbers
.
From
the Encyclopedia of Sports Medicine, the article “Doping and Performance Enhancement: A
New Definition” states,
“Viral expression of

insulin
-
like growth factor 1 (
IGF
-
1) without
resistance training produced a 14.8% increa
se in mass. Combined with training, this produced a
31.8%
increase in muscle mass in mice


(
De Rose
&

Michelucci, 2011, p. 384
).

The
combination of resistance training and the use of IGF
-
1 can increase muscle mass better than
using IGF
-
1 on its own. It is
without a doubt that t
hese numbers are enticing to athletes and
fitness professionals.

Although there are

benefits to
using IGF
-
1 for
muscular hypertrophy
,

however,
its view
as an anti
-
aging agent has significant implications. From the British Journal of
Pharmacology

medical res
earcher
s

Antonio Musaro et al. (2001) states
, “
Skeletal muscle specific expression of
one splice variant of IGF
-
1 in transgenic mice induced marked muscle hypertrophy that escaped
age
-
related muscle atrophy and retained the prolifer
ative response to muscle injury characteristic
of younger animals
(
as cited in
Wells, 2008
, p. 625
).
The implications of
IGF
-
1’s

anti
-
aging
GENE DOPING: AN UNTAMED THREAT


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qualities
would

benefit
the older

population of
athletes
that push their

bodies

to the limit, because
it would help
them prolong their athletic careers
. Also, this could be something that is
marketable to the general population as a new

fountain of youth


protein formula.
Besides the
use of IGF
-
1
,

there is
a

gene that regulates the
potential

size of h
uman
physique
,

including
muscle
size,
called myostatin.


Myostatin is a negative regulator of muscle growth. I
f one can minimize the regulation of
myostatin then the potential for growth would be unlimited.
There
have been many studies

that
have examined

the Belgian Blu
e c
attle and

they have found that

they have more muscle mass
than
the
average cattle.
From the Encyclopedia of Sports Medicine, Eduardo Henrique De Rose
and Marco Michelucci state,
“On examining the expression pattern and sequence of the gene in
normal and

double
-
massed cattle, a mutation within the myostatin gene was found” (
2011, p.
384
).
This shows that
by limiting

the negative regulation of myostatin
,

muscle mass could
potentially
double.
DJ
Wells conveys

the ideas of
geneticist
Dr.
A.C.
McPherron

et al
. (1997)
and Marcus Schuelke
,
M.D. et al. (2004),


Mice in which the myostatin gene has been
inactivated
show marked muscle hypertrophy
and a recent report described similar muscle
hypertrophy in a child carrying mutations in both copies of the myostatin gene
(
as cited in

2008
,
p. 626
).
The fact that a mutation is possible in humans would spark

the most

interest
from high
performance athle
tes that would like to benefit from reducing myostatin’s effectiveness.
Also,
follistatin is a natural agonist to myostatin. By up regulating
, or increasing the amount of

f
ollistatin
and
down regulating
, or decreasing,

myostatin an athlete would be able to

double their
muscle mass.
While one

athlete
might want to

increase
muscle mass,
another athlete may want to
increase cardio
-
respiratory performance.

Erythropoietin
(Epo)
is a glycoprotein that increases red blood

cell

count in the body. It is
GENE DOPING: AN UNTAMED THREAT


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produced in the kidney in response to a low concentration of oxygen.

For example, by i
ncreasing
an athlete

s red blood cell count
, it

will increase
s

the amount of oxygen carrying capacity of
his/her body, thus allowing him/her

to
perform

for longer periods of time. The only problem with
modifying this gene
(
and other genes
)

is that scientists
do not

know how to turn the genes off
once they are turned on. Dr. Garey Bradley, a genetics professor from La Sierra University,
shared, “Th
ere have been studies done on monkeys w
here they had modified the Epo gene
,

causing the

monkeys
to die

because they had
an

over production of blood cells
. They had

no way
of turning off the gene

once it was activated


(personal communication, January 26, 2012).

In
theory
,

up regulation of Epo
is

a winning idea
. I
t is
,

however,

a
nother

contraindication for the
use of gene doping in its present state.
Along with Epo there is another
approach

to enhance
endurance performa
nce.

The

method called peroxisome
-
proliferator activated receptor

(PPAR)

has the ability to
convert muscle fibers from fast twitch muscle fibers to slow twitch muscle fibers, which
would

give an athlete more endurance capabilities.
According to genetics re
searcher Yong
-
Xu Wang et
al. (2004) e
xpression of PPAR in skeletal muscle increased the running capacity of transgenic
mice; almost double that of their wild counter parts from the same litter
.

Inherently, gene transfer
of PPRA in athletes may progress endurance capabilities by increasing the ratio of type I muscle
fibers to type II fast twitch fibers
(
as cited in
Wells, 2008
, p. 626
).
This means of alteration
might

increase aerobic capacity for
long distance runners
. One might ask,
If one looks back at the
history of genetic therapy he/she would fin that this is where the notion of human gene
modification all started.

Gene therapy has been around for almost twenty years. The tools and applicatio
ns
genetic
therapists

use are for diseased people
. All of the techniques
,

such as viral and non
-
viral vectors,
GENE DOPING: AN UNTAMED THREAT


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IGF
-
1, PPRA, Epo
,

and myostatin are the
primary

techniques that have been used to treat
diseases such as muscular
dystrophy
, severe combined immu
nodeficiency

(SCID)
, and

a number
of other genetic disorders.
Unfortunately, there have been more disasters in trying to
perform

these practices on humans than successes. However, one subject showed promise that genetic
therapy c
an work. O
n May 26, 2007
,

Dr. Fabio Candotti
,

from the Gene Therapy National
Institutes of Health
,

treated a young girl by the name of Katlyn DeMerchant who has SCIDs.
Although gene therapy did not completely cure her from the disease, however, it did help to
enable her
to lead a
more conventional life of playing in
the dirt, taking airplane trips,
having fun
with friends, borrow
ing

books from the library and go
ing

fishing with her father (Potter, 2010
, p.
168
). This little girl
’s dream came true.

She now will have the ability to h
ave a

childhood and
live a life outside
constraints
. Most kids with SCIDs have to
live

in a sterile bubble
,

close
d

off
from society and life’s normal processes.
T
he majority of patients
who received the viral vector
platforms

to treat their diseases ended up dying due to the immune system responses to the virus.
This information needs to be used as caution for athletes wanting to use these
methods.

At

the present time there has not been any
recent

advancement with humans. The

main
reason
is because of human ethics. The ethics committees will let people test animals many times
before they will let the first test be applied to a human subject. This is because too many people
have died in the name of science. In essence
,

genetic
doping is still a theory. There are too many
contraindications for its practical use. Now, ethics cannot stop a mad scientist in another country
who can get willing athletes to submit themselves to this kind of genetic alteration. If this were
the case and

gene doping was more than just a theory
,

the world today probably wouldn’t even
know about it until it was put on display for the world to see.

In the book
Designer Genes

by Steven Potter, Ph.D

the author
discusses

super athletes
GENE DOPING: AN UNTAMED THREAT


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and how uniform they wi
ll look amongst the other athletes. He says, “They won’t be
distinguishable from the naturally gifted athletes we see today, except in their extreme abilities”
(2010
, p. 146
). How shocked would the world be to

see an athlete in the Olympic
games

just
shatter a world record without any effort? That individual athlete would be remembered forever
.
To accompany this achievement, the

world would never be able to tell that that athlet
e had been
genetically modified,
and there is no way anyone could pro
ve it.
According to De Rose and
Michelucci
, “Many scientists believed that already in the Beijing Olympics some degree of gene
doping was possible” (
2011, p. 385
).
The
World Anti
-
Doping Agency

has taken preventative
measures to ensure that genetic doping s
tays out of professional sports and especially the
Olympics.

WADA has already banned gene doping. The organization has it listed on its “Prohibited
List 2012” even though they still cannot detect the majority of the platforms. They have funded
research st
udies and come up with ways to detect the modification of myostatin and Epo or
“blood doping.” The
practicality of conducting these tests usually calls

for muscular
biopsies,
which

can be very costly and painful for
the competing athletes
.
Science has come

up with the
idea of using probes to detect transgenic events. Andy Miah states in his book
Genetically
Modified Athletes
, “The basic principle is to introduce a probe into the DNA molecule of the
subject. This probe attaches itself to the subject’s DNA to

reveal disorders in the genetic make
-
up (Macer, 1990)” (2010
, p. 47
).
Even though this statement is referring to detecting genetic
disorders it can be extrapolated to help with detection of gene m
odifications.

There was a study
published in 2011 in the Jo
urnal of Analytical Chemistry that used probes and surface plasmon
resonance imaging to detect specific DNA sequ
ences.

Authors

Simona Scarano et al. (2011)

concluded, “The system successfully
allowed

the detection of specific DNA sequences (EGFP1,
GENE DOPING: AN UNTAMED THREAT


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EGFP2 an
d CMV) on the vector backbone in transgenic HEK [human embryonic kidney] cells,
indicating positive res
ponse to the transgenosis event


(p. 6252).

With this successful
application there is hope for WADA and their detection problems. Scarano et al. (2011)

continues in conclusion
:

In this sense, a possible extension of our approach should be in the direction of the
combination of different probes, by the design of large databases of target sequences
(genes, nonviral and viral shuttle constructs, proteins, et
c.) suspected of being involved,
directly or not, in transgenic protocols for gene doping purposes. (p. 6252)

The author is discussing the necessity of combining different probes to be associated with large
data bases that contain the information of prohib
ited genes, platforms of manipulation, proteins,
and other viable information needed

to detect genetic manipulation in athletes. This study was
funded by a grant given by the WADA to help them with their detection problem.
This begs the
question,

“What can the world expect as we continue into the 2012 Olympics?”

As
previously stated,

scientists believe that there
was

some form of genetic doping
already starting in the 2008 Beijing Olympics.
In developing new techniques for modification
,
four years

is a lot of time for a beautiful mind to improve upon genetic enhancing processes.
According to Potter

(2010)
,

if nothing is done

Olympic records will continue to fall

and fall and
fall again

as our genetic
-
engineering skills improve

and we continue to m
ake better athletes […]
Olympic games will begin to look more like science exp
eriments than a field of heroes
” (p.148)
.

I believe that WADA and the world would agree with these conclusions, however, genetics
professor Dr. Garey Bradl
e
y

of La Sierra Univers
ity
does not

agree. He states, “The world
thought it was possible in the 80’s and now a little over twenty years has gone by and we still
haven’t be
en able to accomplish this feat


(personal communication January 26, 2012
).

GENE DOPING: AN UNTAMED THREAT


11

Professionals may disagree, but
the world may never know until
it is showcased for all eyes to
see.

The theory of genetic doping is still very much a theory. There have been successes
coupled with even more failures. All of the processes
and platforms associated with genetic
doping take

on inherent risks that athletes should be forewarned about. The thought process may

be the same as th
ose who choose to use steroids
. In this case one could try to inform athletes
of
the negative consequences,
but they are going to do whatever it takes to get to the top. Genetic
doping is definitely the new platform to achieving that ultimate goal. It is unfortunate that the
tools

of genetic therapy, which were invented to do

good
”,

are now being implemented to

do
inherently

bad


things.
Even though scientists do not have the means to successfully perform
genetic modification

safely
, hopefully

the technology they do have is enough to detect instances
of abuse.

Society definitely needs to be aware
that

the poss
ibilities of genetic doping are eminent
and it is only a matter of time before the world’s
best
-
kept

secret is going to be
exposed
.

The
disadvantages of gene doping for a high level athlete, at this stage in the technological process,
are not great. An ath
lete would be better off training hard because the dangers to gene doping are
very drastic. Not one person has been successful in safely modifying an athlete’s genes that
science has documented.
Professionals claim that genetic doping has already been succ
essfully
completed, as of the 2009 Beijing Olympics.
If gene doping were possible, the advantages would
be theoretically l
imitless.

An athlete’s abilities would look like something out of a scientific
movie because no one has ever seen it before. The Olymp
ic games would look more like a
competition full of science experiments than athletes humbly competing for the pride of his/her
country.
What better place to showcase “super
-
human” like talent than in the London Olympic
GENE DOPING: AN UNTAMED THREAT


12

games of 2012?


Running Head: GENE DOPING: AN UNTAMED THREAT

13


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