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Does our genetic make up determine who we become?

asavannah's picture

       Have you ever wondered where you get your physical or behavioral traits from? Well I have and I decided to do more research on this topic which is what this paper would be about. I am going to discuss the difference between nature versus nurture and whether one or the other has a greater impact on the way an individual behaves. This topic also became of interest to me when I decided to focus more on the study of identical twins who have the same genetic make up but not necessarily the same interests.
       The idea of nature versus nurture has been puzzling to scientists for a very long time. “Nature” the idea that was viewed by most people in the beginning of the twentieth century, states that a person’s behavior comes from their genetic traits and that the environment has absolutely no affect on their life. “Nurture” on the other hand is the idea that a person will develop their behavior from outside environmental factors and not necessarily from genetics.
       The study of nature versus nurture is usually tested on identical twins. Identical twins are also called monozygotic twins; which means that they derived from the fertilization of one egg by a single sperm which then created a zygote that was split into two embryos. These two embryos now share the same genetic material. It is important to know that just because the monozygotic twins have the same genetic make up, that one should not automatically assume they are exactly the same when it comes to their personality.  
       For example, in my immediate family, we have a set of 5-year-old identical twin boys, who look very much alike with minor differences and have totally different personalities; one being very outgoing, talkative, and active, while the other is more timid, quiet, and reserved. They also have different physical traits for example one is taller than the other. From observing my nephews I noticed that some of similarities they have are their physical features; they are both also very inquisitive and have a zeal for learning.
       I believe that their differences come from their environment. Even though they live in the same household they have been placed into separate classes at school which means they are learning different material in different ways. Many schools actually encourage that twins be placed in separate classrooms so that they can form their own identities.  They also have very different interests; one is very interested in dinosaurs while the other enjoys learning about the solar system. While they are still pretty interested in what the other likes, they will both return back to their original interest. 
       For the nature versus nurture test for the identical twins that do not live in the same household because they were probably split at birth may have a great difference in personality. If one twin was reared in a household that eats meat products, follows a certain type of religion, and is involved in numerous amounts of school activities; this child would have different views of life compared to the other twin, who may be a vegan, may follow some other religion, and does not take part in school activities. This example proves that the environment in which a person lives has a great impact on their personality.
       This study of a set of identical twins that were separated during birth or raised in different households has not always had the same results. Sometimes they find that the set of twins indeed have similar personalities, occupations, interests, and mannerisms even thought they were brought up separately. This study goes on to prove that genetics does still play a significant role in the traits that are possessed by a particular individual.
 The idea of certain genes being switched on or off due to particular environmental influences is called epigenetic modification. This means that monozygotic twins who share the same DNA can possibly be very similar or different due to the impact their environment has on their lives.
       A study that was conducted with twins ranging from ages of 3 to 74 showed that the youngest twins have fewer epigenetic differences. This could be due to the fact that the children do not have much life experience and that they possibly follow what the other twin does. The test also proved identical twins that increased in age had a greater epigenetic difference; this is due to the different exposure each receives to a variety of things in life. The study also showed that twins who were raised separately had the greatest difference. But with age they also found that characteristics such as IQ became more alike as twins got older which then again proves that genetics still has a lot of influence.
       From the research I did on this topic I found that neither nature nor nurture has more influence over the other but instead they work together. As we can see from the studies done on this topic, identical twins who share the same genetic make up are not exactly the same or totally different. They may share some traits and not others and now we know that we cannot completely rule out the idea of genetics or environmental influences because they are both equally important to our physical and behavioral traits. 




Dr Mervyn J Edwards's picture

re your article

Good morning I am very interested in featuring your article in my next book. I wish to seek permission to feature your article.

Sincerely yours
Dr Mervyn J Edwards

white Pearl's picture



Jasmine's picture

Epegenetic modification in personalites of monozygotic children

This is very interesting. Do you have any references that you used regarding this study?