"Kyle Legate" <[email hidden]> wrote in message
"]news:[email hidden]...
Quoted message said:Quoted message said:
The key, they say, is genetic manipulation. By the Athens Olympics in 2004, dozens if not
hundreds of athletes are expected to have experimented with the rapidly emerging range of
gene-altering drugs. Unfettered by fears of being caught they will, according to the experts,
shatter the accepted limits of human performance.
No.Maybe by the _next_ Athens Olympics, but not these ones. The technology is not there yet. What you
quoted was an ill-informed piece of fluff.
Dumbass -
perhaps, but its being speculated about all over the 'net. If people are thinking about it, that
means that somewhere, someone is going to try it, sooner rather than later.
maxmag.maxsportsinternational.com28sci1.htmOpen ↗
With relatively few old-timers showing an inclination to pump iron three times a week for the rest
of their of lives, the potential market for an alternative muscle-building drug is clearly enormous.
Science finally appears close to creating one.
In separate experiments over the past couple of years at the University of Pennsylvania Medical
Center in Philadelphia, and University College Medical School in London, as well as the Copenhagen
Muscle Research Center in Sweden, researchers have tested muscle-building vaccines based on
engineered genes. Injected into mice, these vaccines have boosted muscle mass in the animals legs by
15 to 27%. Amazingly, these increases were measurable in only a month or so and did not require any
exercise at all! Many muscle researchers believe that the first human trials will occur within the
next couple of years. This could also be a major breakthrough for the treatment of a host of
degenerative muscle diseases, including the various forms of muscular dystrophy.
On the down side, it takes little imagination to see the possibilities for abuse of the vaccines by
healthy young athletes in power sports such as football, weight lifting, sprinting and
short-distance swimming. Compared with anabolic steroids, a vaccine based on an engineered gene
would offer some major advantages. It would need to be administered only one time, rather than
periodically, and it would be essentially undetectable in the body.
MUSCLE PHYSIOLOGY 101
A single muscle cell consists of a membrane, many scattered nuclei that contains genes and thousands
of inner strands called myofibrils. Filling the inside of muscle fiber, the myofibrils can be as
long as the fiber and are the part that enables the cells to contract forcefully in response to
nerve impulses. The actual contraction is accomplished by the myofibril tiny component units which
are called sarcomeres. Within each sarcomere are two proteins, called myosin and actin, whose
interaction causes contraction of the muscle. Basically, during contraction a sarcomere is shortened
like a collapsing telescope, as the actin filaments at each end of a central myosin filament slide
toward to the myosin's center.
Muscle cells, also known as fibers cannot split themselves to form completely new fibers. A muscle
can become more massive only when its individual fibers become thicker. What causes this thickening
is the creation of new myofibrils. The mechanical stresses that exercise exerts on tendons and other
structures connected to the muscle trigger different biochemical pathways that ultimately cause the
muscle cells to make more proteins.
Enormous amounts of these proteins, chiefly myosin and actin, are needed as the cell produces
additional myofibrils. As muscle cells cannot divide, the new nuclei are donated by so-called
satellite cells, which are scattered among the many nuclei on the surface of a skeletal muscle
fiber. Satellite cells proliferate in response to the stresses and wear and tear of exercise. As
they multiply, some remain as satellites on the fiber, but others become incorporated into it. With
these additional nuclei, the fiber is able to turn out more proteins and create more myofibrils.
Rigorous exercise inflicts tiny "micro tears" in muscle fibers. The damaged area attracts the
satellite cells, which incorporate themselves into the muscle tissue and begin producing proteins to
fill the gap. Gradually, as more micro tears are repaired in this manner, the overall number of
nuclei grows, as does the fiber itself (i.e. muscle enlarges).
One component of the myosin molecule, the so-called heavy chain, determines the functional
characteristics of the muscle fiber. In an adult, this heavy chain exists in three different forms,
known as isoforms. These isoforms are designated Type I, Type IIa, and Type IIx, as are the fibers
that contain them.
Type I fibers are also known as slow fibers; Type IIa and IIx are referred to as fast fibers. The
fibers are called slow and fast for good reason; the maximum contraction velocity of a single Type I
fiber is approximately 1/10th of every Type IIx fiber. The velocity of Type IIa fibers are somewhere
between those of Type I and IIx. Slow fibers depend more on relatively efficient aerobic exercise
where as the fast fibers depend more on anaerobic exercise. Thus, slow fibers are important for
endurance activities and sports such as long distance running, cycling, or swimming, where as fast
fibers are key to power pursuits such as weight lifting and sprinting.
The "average" healthy adult has relatively equal numbers of slow and fast fibers in say the
quadriceps muscle of the thigh. But as a species, humans show a great variation in this regard. A
person with a predominance of slow fibers would probably become an accomplished marathoner but would
never get anywhere as a sprinter or power lifter; the opposite would be true of a person with the
predominance of fast fibers.
MUSCLE CONVERSION
When healthy muscles are loaded heavily and repeatedly, as in weight training programs, the number
of fast IIx fibers declines as they convert to fast IIa fibers. In those fibers, the nuclei stop
expressing the IIx gene and begin expressing the IIa. If vigorous exercise continues for about a
month or more, the IIx fibers will completely transform to IIa fibers. At the same time, the fibers
increase their production of proteins, becoming thicker (hypertrophy).
CONVERTING SLOW TO FAST?
Is it possible to convert the slower Type I fibers to faster Type II fibers? In the early 1990's
there was an indication that a rigorous exercise regimen could convert slow fibers to fast IIa
fibers. Researchers at the University of Copenhagen Muscle Research Center suggested that a program
of vigorous weight training supplemented with other forms of anaerobic exercise converts not only
Type IIx fibers to IIa, but also Type I fibers to IIa. If a certain type of exertion can convert
some Type I fibers to IIa, we might naturally wonder if some other kind can convert IIa to I. It may
be possible, but so far no link in human training studies has unambiguously demonstrated such a
shift. It is true, star endurance athletes such as long-distance runners and swimmers, cyclists and
cross-country skiers generally have remarkably high proportions (up to 95%, as mentioned earlier) of
slow Type I fibers in their major muscle groups, such as in the legs. Yet at present we do not know
whether these athletes were born with such a high percentage Type I fibers and gravitated toward
sports that take advantage of unusual inborn traits or whether they very gradually increased the
proportion of Type I fibers in their muscles as they trained over a period of many months or years.
Researchers have found that hypertrophy from resistance training enlarges Type II fibers twice as
much as it does type I fibers. Thus, weight training can increase the cross-sectional area of the
muscle covered by fast fibers without changing the relative ratio between the number of slow and
faster fibers in the muscle. It is the relative cross-sectional area of the fast and slow fiber that
determines the functional characteristics of the entire muscle. The more area covered by fast
fibers, the fast and more powerful the overall muscle will be. So a sprinter at least has the option
of altering the characteristics of his or her leg muscles by exercising them with weights to
increase the relative cross section of fast fibers.
THE ERA OF GENETIC MANIPULATION
Although certain types of fiber conversion, such as IIa to I appear to be difficult to bring about
through exercise, the time is rapidly approaching when researchers do have the capability to
accomplish such conversions easily through genetic techniques. Such genetic manipulations, most
likely in the form of vaccines that insert artificial genes into the nuclei of muscle cells, will
almost certainly be the performance enhancing drugs of the future. The tiny snippets of genetic
material and the proteins that gene therapy will leave behind in the athletes muscle cells may be
difficult, if not will be impossible, to identify as foreign.
Gene therapy is now being researched intensively in most developed countries for a host of very good
reasons. Instead of treating the deficiencies by injecting drugs, doctors will be able to prescribe
genetic treatments that will induce the bodies own protein-making machinery to produce the proteins
needed to combat illness. Like ordinary genes, the artificial gene consists of DNA. It can be
delivered to the body in several ways. Suppose the gene is encoded for one of the many signaling
proteins or hormones (testosterone or growth hormone) that stimulate muscle growth. The approach
would be to inject the DNA via vaccine into the muscle. The muscle fibers would then take up the DNA
and add it to the normal pool of genes.
This method is not very efficient yet, so researchers often use viruses to carry the gene payload
into a cells nuclei. A virus is essentially a collection of genes packed in a protein capsule that
is able to bind to a cell and inject the genes. Scientists replace the viruses own genes with the
artificial gene (i.e. the muscle growth stimulator gene), which the virus will then efficiently
deliver to the cells in the body.
GET PUMPED THE EASY WAY
It is easy to see how the narcissist would find the drug irresistible. A vaccine to build muscle
mainly where it was injected, making it possible for even the lazy and uncoordinated to sculpt their
bodies by doing nothing more strenuous than lifting a hypodermic needle. Big biceps, nice calves and
big bulging pecs would all be just a few injections away. Of course, an instant physique of this
kind would not come without a physiological price. To improve performance or look really buff,
athletes and body builders would probably need to take considerably larger doses than what doctors
will prescribe for therapy. Thus, they would probably suffer some of the already known or suspected
side effects for abuse of IGF-1, such as an enlarged heart and possibly cardiac arrest.
THE GENETICALLY ENGINEERED SUPER ATHLETE
These techniques will be abused by athletes in the future. Sports officials will be hard-pressed to
detect the abuse, because the artificial genes will produce proteins that in many cases are
identical to the normal proteins. Furthermore, only one injection will be needed, minimizing the
risk of disclosure. It is true that officials would be able to detect the DNA of the artificial gene
itself, but to do so they would have to know the sequence of the artificial gene, and the esters
would have to obtain a sample of the tissue containing the DNA. Today, however, biopsies are not
permitted as part of a routine anti-doping test. For all intents and purposes, gene doping will be
undetectable.
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