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Unnatural Selection

lcorhan's picture


Human genetic engineering is the act of modifying an individual’s genes (genotype) in an effort to choose a certain characteristic (phenotype). In the not-so-distant future, it will be possible to choose every characteristic of one’s children. Although genetic engineering is commonly accepted for fighting disease, even this is can be ethically debated. An even cloudier issue is that of choosing aesthetic traits like height and eye color. The implications of this would certainly be ground breaking and perhaps catastrophic.
Although using genetic engineering for fighting disease seems like a very noble cause, it empowers humans to make very difficult choices. Certainly the choice to delete the gene for type 1 diabetes from a child’s genetic code is an easy one to make. But what about dwarfism? It’s hard to imagine parents choosing to have children who are dwarves. Yet on a societal scale, with each parent choosing to have children without the dwarfism gene, society as a whole is deciding that dwarfism does not serve a purpose. Society will effectively and actively do away with dwarves.
The idea of society choosing which traits belong and which do not is very troubling. While parents don’t currently choose to have children who have dwarfism or Down ’s Syndrome, most end up being happy that things ended up the way they did. It is troubling to think that we would rid ourselves of such enriching experiences and such diversity in the world, but this is inevitably what would happen should humans be given such power. This matter becomes even more terrifying when the concept of choosing a child’s race before he or she is born is brought into question.
Choosing aesthetic traits gives birth to a similarly troubling issue. First of all, if parents can choose the height of their children, then it is reasonable to predict that the number of women who grow to be over six feet tall would rapidly plummet. People with low cheek bones (generally considered less attractive) would become more scarce. Clearly, the amount of genetic diversity in the world would decrease dramatically.
Aside from the issue of decreasing genetic diversity, the ability to choose traits that used to be determined at random brings up another disconcerting consequence. By giving humans the ability to choose how tall their children will be and what color their hair will be, we are essentially high-jacking natural selection from Mother Nature. This unnatural selection is frightening because we wouldn’t want to live in a world where everyone looks the same. Nonetheless there is still yet a much scarier and more serious consequence.
Natural selection is a very important system of weeding out ineffective characteristics. It would seem as if genetic engineering would expedite this process because we would lend a helping hand to Mother Nature in selecting which characteristics are undesirable. On the contrary, we would actually be throwing a wrench in the gears of the natural selection machine.
Natural selection is driven by genetic diversity. The traits that do not help a species prosper eventually disappear due to individuals with that trait being less likely to reproduce and pass on the genes that accompany it. Of course, favorable traits on the other hand become more prevalent. These two phenomena lead to a species becoming more fit for the world. By virtually ending genetic diversity, neither of these phenomena will occur and we will freeze the natural selection of homo sapien sapiens at its current state. Clearly this is not a decision that humans have ever had to make and it doesn’t seem like one that humans are adept to make.
The idea of ending natural selection doesn’t seem too terrible at first, because human beings seem to have it pretty good. The implications, however, would certainly be catastrophic. The idea of missing out on potential genetic enhancements is rather depressing, but the horrible part is that the human race would be in grave danger. Part of the genius of Mother Nature’s plan of natural selection is that there is strength and security in diversity. Just as the Bubonic Plague simply left some people alone while rapidly killing others, diseases only affect certain genotypes. With everyone sharing the same genes, epidemics would be far worse, especially in our globalized society. Eventually, this chain of events could lead to human-kind’s undoing.
            There must be very fine lines and serious ground rules present if we decide to utilize genetic engineering. The possibility of forever ridding the world of diabetes, cystic fibrosis, and other terrible diseases is one that we simply cannot ignore. But, while genetic engineering could make life so much better for human-kind, it could also end it all together. Ultimately, genetic engineering should be used as a form of preventative medicine and nothing more.


Paul Grobstein's picture

Genetic selection by humans

Important argument.  But what about the genes involved in diabetes, cystic fibrosis, etc?  Might they not also be contributors to the genetic diversity on which human evolution depends?