Shenk explains that, “The public has gotten the impression
that the answer to almost every question about our health and well-being can be
found in our genome (p 180, The Evidence).” As we learned in our inheritance (Chapter
16) and genetics units (Chapter 17, 18, & 20) the progress in the field of genetics
has provided a lot of information about the human genome and also how to alter
it. Do you believe that we have a better a better control today over who we
become as a result of this information? Do genes provide more information about an individual than external
influences during daily life? Do you believe that it will be
possible to determine the behaviour of individuals based on their genes? Refer
to recent studies and also information we have talked about in class about
genetic engineering techniques and the advantages they can provide for humans.
It is true that our the genes receive from our parents plays a crucial role in how our lives turn out today, and this information about our DNA has become accessible through new technology. After all, using a pedigree, or "a family tree describing the traits of parents and children across the generations," we can track genetic diseases that run through our family (Campbell 276). Furthermore, our DNA can be sequenced through the Sanger process, and the genetic code we have can be split into codons to see what amino acid chains and proteins we can create. This information can tell a lot about an individual...
ReplyDeleteBut not all of it. Although genes code for the proteins that give s our traits, Shenk says, "Genes, proteins, and environmental signals (including human behavior and emotion) constantly interact with one another, and this active process influences the production of proteins" (31). Thus, it is seen that both genes and environment determine the nature of an individual, not one over the other. Furthermore, as genes only code for proteins, there would be a indirect factor from knowing one's behavior when looking at his genetic code, and so one's behavior would be hard to predict by just looking at the genetic code. Furthermore, if knowing genes meant knowing the behavior, then wouldn't everyone, because they have nearly all the same genes, behave in the same way?
Behavior is instead initiated by both genes and environment. Through the biological theme of regulations, regulatory mechanisms switch genes on and off, depending on environmental stress, causing the production of proteins and behavior mechanisms. Furthermore, as behavior is caused by environmental stresses, the theme of interdependence in nature also is present.
Knowing one's genes, or mutations the genetic code, though, isn't necessarily useless in predicting behavior. Many offspring tend to live in similar, if not the same environment of the parent, and with this common environment, the genes that were on should be on and the genes that were off should remain off. As a result, behavior disorders can be seen to have a correlation with genes. One experiment shows that genes have an major effect on behavior, as "both genetic disruption and acute pharmacological blockade of the NK1R in mice result in a marked reduction of anxiety and stress-related responses" (http://www.pnas.org/content/98/4/1912.full?sid=f5ecb265-5f38-43e3-8259-51cfdb631b9d). Therefore, if one knows that the gene in a specific environment will lead to a specific behavior, then one's knowledge of that gene will be useful in predicting future behavior.
Matthew Yang (matt.y.yang2013@gmail.com)
I agree with Matt on the fact that genes play a crucial role in how our lives turn out today. A pedigree really does help in identifying certain inheritable diseases (Campbell 276). Interestingly, there are a lot of mechanical events happening when it comes to genes and inheritance. According to all of the information that we’ve learned from Campbell throughout the year, we receive a mix of genes from our parents, and through these genes everything is determined, from physical appearance to talents to weaknesses. However, Shenk is arguing that although genes do play a crucial role, environment also has a huge role as well.
ReplyDeleteWith the information about how to “change” the human genome, I doubt that it really gives a better control today over who we become. Perhaps one day, people will be able to mix and match the genes that they want in order to form their idea of a perfect child. However, at this moment, we are learning that our genes are absolute and “our genes are blueprints that make us who we are. Different genes make us into different people with different abilities” (Shenk 10). At this point, we are resigned to the idea that Tiger Woods has some prodigal talent with gold, Michael Jordan has an amazing affinity for basketball, and Mozart was born to be one of the greatest performers and composers in history. Instead, the GxE theory seems to be a theory that will foster change. The GxE theory shows that “talent is a not a thing; it’s a process” (Shenk 10). Instead of resigning ourselves to fate and inevitability, the GxE model teaches us that it’s up to us to become these geniuses, through hard work and perseverance.
PART ONE
Annie Lee (xxannie.leexx@yahoo.com)
Now, this does not mean that genes do not matter as a whole. Behaviors, appearances, and characteristics can be predicted through genetics. Genes, which we are born with, give us the base to begin building off of. However, I truly believe that environment affects us more as people. External factors ultimately shape who we are. If genes are our foundation, environment constructs our house. The Risley and Hart study showed that children who were raised in professional homes became more intelligent than children who were raised in welfare homes. This disparity was encouraged by the difference in number of words spoken around the house, as well as the quality of the words. In addition, the number of encouragements given to children in each household was always larger in the professional homes (Shenk 46-47). The environment around them caused the children to become more intelligent. Genes are “knobs and switches [that] can be turned up/down/on/off at any time” (Shenk 19). The children from the welfare homes may have had an affinity for extreme intelligence; however, due to the lack of stimuli, the welfare children wasted their potential.
DeleteDue to this extreme importance of external stimuli, I think that it’s very hard to determine the behavior of individuals based on their genes. It won’t be impossible, but it will only be for special cases. Many people change multiple times during their life. They may begin meek and quiet at a young age, and then become social and outgoing during high school, only to become meek and quiet again once they reach adulthood. Of course, genes provide natural predispositions. For example, it was found that there are genetic influences on criminal activity. However, environment played a role, but it was a role smaller than genetics “http://www.sciencedaily.com/releases/2012/01/120125151841.htm). Even in the short term , stimuli change things. Scientists asked parents to rate children on hyperactivity levels. Then, the parents were told that the children were given sugary drinks to consume. Despite the fact that the drinks were sugar-free, parents rated the children more hyperactive than before (http://www.cbc.ca/news/health/story/2008/12/17/festive-myths.html).
Matt brought up the point that "both genetic disruption and acute pharmacological blockade of the NK1R in mice result in a marked reduction of anxiety and stress-related responses" (http://www.pnas.org/content/98/4/1912.full?sid=f5ecb265-5f38-43e3-8259-51cfdb631b9d). In twins, scientists try to “ estimate the heritability of a trait, but molecular genetics attempts to pinpoint the effects of a particular gene” but at the same time, “acknowledge that [there are] limitations [that] exist” (http://www.apa.org/monitor/apr04/second.aspx).
Genetic engineering is widely used in regards to food. Everything from corn to cattle is genetically modified, in order to produce the most with the least amount of resources and effort. However, in humans, we still continue to struggle with the idea of morals.
Overall, genes do help determine what you will be like, and people may make predictions on what you will be like based on your genes; however, genes and environment are both important in developing your character.
In regards to the biological theme of evolution, genetic engineering will definitely give humans advantages. By placing genes that have affinities for particular activities within a human, that human now has that much potential, and everyone will be brought up to a new standard of ability. Although, due to the plasticity of the brain, I think we’ll be alright.
PART TWO
Annie Lee (xxannie.leexx@yahoo.com)