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Genetic Engineering as the End of Human Evolution?

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The Story of Evolution, Spring 2005
First Web Papers
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Genetic Engineering as the End of Human Evolution?

Tonda Shimbo

In order to have any evolution of a species whatsoever, there must be some sort of mutation. Granted, the majority of mutations attempted by a species fail miserably and the individual plant/animal will not survive, but without mutation, the gene pool is limited – stagnant even, and when the gene pool is stagnant,, there is less chance for survival, and evolution essentially stops (Mayr, (1)).

With that in mind, and the entirety of evolutionary processes, what are we humans doing in the field of genetic modifying medicine? Gene therapy may help a lot of people live out healthier, happier lives (Anderson, (2)), but is this helping evolution? Hurting it? Will our supposed health happiness in the present bring suffering and death for the future of our species? It is a difficult idea even to wrap one's mind around. Of course we want to help our brethren to feel less pain – to use gene and small molecule therapy (see Anderson, 3rd paragraph for definitions) to take away 'genetic diseases' just as one would use Tylenol to take away a headache or a fever – it is the compassionate, humane thing to do. But where do we draw the line between that and the facts of life – death (even young death), diversity in the gene pool (including mutations – attractive or not), etc.?

Reproductive medicine has raised a lot of bio-ethical questions over the past forty or fifty years. From birth-control to Roe v. Wade to test-tube babies to choosing the sex and other genetic traits of one's child (Caplan & McGee, (3)), many wonder where we are going with all of these technological advances in medicine. Are we perhaps becoming too smart for our own good? Recently a 66-year-old woman gave birth to a child in Romania with much help from her doctor as she was too old to create her own eggs – an egg was fertilized and then placed into her uterus (Caplan, (4)). She will be eighty when her daughter enters high school. This may be pushing the question too far towards the bio-ethical standpoint, but nevertheless, where do we draw the line in reproductive medicine? Do we allow, a hundred years - or maybe even decades – from now parents to essentially create their own children by choosing eye color, hair color, intelligence and strength through the simple selection and rejection of genes? From an evolutionary standpoint, this process could alter – even stop completely – the process of human evolution, for it would disallow mutations in pursuit of the 'perfect' child.

Residing in Germany is a four year old boy who was born with a genetic mutation that prohibits production of myostatin (a protein which limits muscle growth), and thereby can hold 7lb. weights in his hands with arms straight out (The AP, (5)). His mother, a former professional sprinter, had one copy of the gene mutated, while both of his are such. This mutation could be a very good addition to the human gene pool. It would allow the human species to; very slowly (as evolution always works very slowly) become a stronger species, which would aid our survival. But then, after chance and natural selection take their course, no one could ever predict whether it would be the gene to survive. Yet, without mutation, the gene pool is limited, and thus the species has a lesser chance of surviving. Many would argue that in our extensive and expanding research on the human genome, one could in effect allow for the strengthening of the species in locating and manually mutating the genes which controlled production of myostatin, and any other factors. However, I would dare to claim that the practice would still limit variation (the key to evolution, along with mutation) in that it would disallow any new mutations from occurring. If a doctor or scientist noticed an oddity in the development of an embryo, he or she would more than likely abort the process and start over again, for fear of the child developing with some horrid and unknown genetic disease. The problem is just that – if it's unknown, we can't be sure that it will end up quite so tragic as the victims of sickle-cell anemia, muscular dystrophy, or any of the other genetic diseases discovered thus far. We can't be sure that it won't have a profound and everlasting positive effect on the human species as a whole.

What does all of this say to the future of our species? Or, for that matter, to the practice of genetic engineering? Should we change the genes of those suffering from genetic disease? Or should we call it an act of chance and evolution, and allow selection to take its course? I fear that if we find a cure for all diseases, our tiny planet will become overpopulated and though we may be healthy, we'll be cramped, claustrophobic, and quite unhappy. Yet I also don't like the idea of anybody suffering from disease. I almost want to make the claim that disease is the natural way of limiting a population, so that it doesn't get out of hand, and that those who can survive – those whose immune systems are tough enough to handle what gets thrown at them, are biologically and genetically superior (though I understand that a great deal of one's ability to deal with disease has to do with the environment in which he or she resides), and that is the way evolution, nature, and perhaps whatever deity is up there intended it (that is to say, if there was intention at all). Perhaps it is like the tsunami – the world's way of recycling and regenerating itself, and though up close it seems tragic and even catastrophic, in the long run it is the best course to take, and will eventually even itself out in order to produce a more adaptive, efficient species.


1) Mayr, Ernst. What Evolution Is. New York, New York: Basic Books, 2001

2)A Cure that may Cost us Ourselves Anderson, Dr. W. French, Newsweek: Jan. 1, 2000

3)Reproductive Medicine Caplan, Arthur L., and McGee, Glenn.

4)How Old is Too Old to Have a Baby? Caplan, Arthur Ph.D.

5)Genetic Mutation Turns Tot into Superboy The Associated Press

6)Future Direction in Bio-Ethics Caplan, Arthur L., and McGee, Glenn.



Continuing conversation
(to contribute your own observations/thoughts, post a comment below)

06/22/2005, from a Reader on the Web

I personally think that genetic engineering is quite a good thing. I can understad that people are afraid of the unknown, but ifwe never step outside the box nothing will ever get done if we are uncomfortable with doing it. so lets all step out of the box and HAVE FUN WITH GENETIC ENGINEERING!!!!!!!!!

Additional comments made prior to 2007
Hi, I totally disagree to genetic engineering. how can we take such risk into producing duplicates of a human being? Cloning, a perfect world all sounds fun and exciting, but this gives opportunity for firstly to people who can use it for their own advantage and to do evil. Secondly we are playing God, and thirdly we don't know what the outcome may be as natural selection will takes it time to process, if we apply GE, we will radically change the biosphere and chaos will not be too far! ... Daron Lew, 8 October 2007


Clark's picture

Pointless Arguments.

I have to agree with Chris on this subject. Although I see genetic engineering as, if we are capable of doing it to advance and aid the health of fellow human beings then we should do it. However, Chris states that providing the correct amounts of nutrition for this (cloned) individual, would not be worth the costs in the long run. Although we may be doing God's work, God gave us the ability the adapt our minds. If we have a headache, should we not take Tylenol because it is a synthetic aid?

Serendip Visitor's picture

The human phenotype

Given the concept of natural selection and its propensity to kill off the unfit it seems unlikely in the highest that a body such as ours could ever have survived the rigors of life in the bush for any length of time let alons long enough for us to stumble into the most unfit configuration for life in nature and the most fit for life in civilization of creature on earth.
Given what we know about mutations their rate, their profound tendency to corrupt genomes and produce disease death or genomic degradation,combined with what we know about genetic engineering and the ability of intelligence to order systems, it is sheer idiocy to presume that stupid Design could compete with Intelligent Design.
We KNOW which one works and we KNOW the odds against random mutations producing order from chaos.

Chris's picture

Are you thinking, maybe, of another term?

Did you mean human genetic mutation? Because evolution is a process in which a sample with qualities deemed unacceptable by an environment stops being, leaving only the acceptably adapted specimens (through the very virtue of being adapted, obviously). A rock falling is a stage of evolution. The environment is our physical universe, and the drive behind the (rather short) stage is gravity.

To limit the entire concept of evolution by constraining it to a natural selection of species in a closed environment, based on genetics, and viewed from an endpoint rather than as a whole, well, to me seems kind of silly.

To carry on and address your topic: no, nothing can stop evolution. Evolution is in everything from photon decay to human genetics to the size and shape of the three dimensional universe. We can't alter evolution, because we can't alter the entirety of the universe, and its myriad laws (yet). Evolution is a concept, a meme, and yet it's also a universal rule (or can be viewed as one) apart from human understanding or observation. When there is nothing around to observe it, a rock with no opposing force still falls towards the ground.

We may be able to choose the path we take towards whichever final destination consciousness and matter is heading with genetic manipulation, and later on through advanced technologies such as nanotechnology and bionics, but matter and energy will eventually decay regardless of how long humans live, or how 'perfect' we are.

In an aside, the reference to evolution always working very slowly is one I'm calling out.

One, define slowly. Humans evolved from mud in only 4 billion years. It's been 14 billion years since time began, and stars are still stars, black holes are still black holes, 99% of all hydrogen is still hydrogen, and gravity is still largely a property of mass. In comparison to the changes of these other natural inhabitants of the universe, we've sprung up and changed quite quickly . In purely genetic cases, look up the reptiles brought from one island to another, where within a few short generations, they began to mutate into a more predatory animal (link provided).

Two, the genetic trait in question would be largely detrimental to human health - you failed to mention the incredible amounts of food required to fuel the activity and growth of such individuals.

Three, evolution obviously can happen quite quickly (as in the case with the falling rock).

In response to the comments above me - The most viable form of genetic engineering is choosing a mate. Should we stop doing that, as well? Think of the consequences! All of those children with genetics that may turn out to be better than the generations before them!

Anonymous's picture

GE the end of evolution?...I think not.

Why would GE or how would GE prevent mutation? You would make disease resistant humans and then you think our genes would stop mutating? How so? Before all these crazy diseases we have today our genes mutated. That's what genes do, we don't have the power to prevent gene mutation first of all.

MOST Gene mutation is a spontaneous process during replication of DNA and some occur from exposure mutation-causing agents such as x-rays or radiation exposure.

Disease at this time isn't controlling population at all, but, it could be disease that one day eradicates or puts us on the brink of extinction. According you we should just let disease rule us and do nothing. Your claim that some immune systems may be superior and they will determine the evolution of billions of people around the world is wishful thinking. That's just not how it works in our time, maybe it used to work that way in the days of early homosapiens or before. Those days are long gone.

One could make the arguement that our ability to follow natural selection has been diverted due to many reasons. People don't chose based on what we percieve to be the original process but, now people choose who to mate with based on money, looks, and availability. Is that really natural selection? No.

If we wait 1000 years or whatever for the Earth to wipe us down to a few just so we can evolve again then what a waste and major set back we would have been. GE is one way that we can force evolution and still have natural gene mutation, you may not like the end results but, by the time it happens you'll be long gone and your opinion will not matter.