Benefits And Dilemmas Of Human Twin Studies

Table 3-1 examines the correlations between selected characteristics for the identical twins separated at birth and the twins raised together. When compared to each other, they both have very similar brain wave activity, blood pressure and heart rate in the physiological characteristics. The Raven intelligence test was very similar, but the WAIS IQ displayed a bit of difference when compared to the other comparisons made. Personality wise, they typically had similar personalities at the same rate as twins raised together. Psychological interests were off a little bit, but still very similar. The twins that were separated at birth had less similar psychological interests compared to the twins

Parallel to this, the focus on genetics is Particularly convicted in twin studies, which establish a comparison between monozygotic twins that are identical and dizygotic twins, which are opposingly non-identical. This distinction can be identified in Torgersens study, which compared MZ and same sex DZ twins where one proband had an anxiety disorder, and it was discovered that such disorders were 5x more frequent in MZ twin pairs, who mutually shared identical genetics.

The Minnesota Twin Registry started in 1983 and its goal was to establish a registry of all twins born in Minnesota from 1936 to 1955 to be used for psychological research.., T.J. Bouchard, working in conjunction with the University of Minnesota, started exploring the similarities and differences in characteristics like personality, career interests, and a variety of personal interests between identical twins who were reared apart. Research was conducted on twins from all over the world. The Minnesota Twin study gave scientists a new insight of the role of nature vs. nurture on human development and personality; it was the hope that twin studies would be able to tie genes to specific behaviors. From the study, we understand that twins who were separated at birth and raised in different families

In reading stories about identical twins my point of view is easily understood. Various types of psychologist have analyzed the study of identical twins. It shows that individuals with the same genetic make-up can be totally different, when it comes to personality. Nurture promotes the twins to grow up as separate individuals. Its a lot better if a twin has his or her own personality rather than the same exact personality of the other half. I think this great debate weighs heavier on the nurture side. As a child my parents, and sibling overshadowed my genetic make-up. No matter how much I thought my physical traits made me behave. It did not affect me more than the things that I had seen and been exposed to. The more things that I had seen around and experienced made me the person that I am today. If my genetic make-up was totally different, to a certain extent, I am sure that I?d behave the same way that I do presently. There are exceptions to that. For instance if I were six foot five and one hundred and ninety pounds, I?d most likely be in the NBA and be really rich. I think if I was really rich and in the NBA I wouldn?t have the same worries that I have today. Even if before I were in the NBA I would have lots of attention and have a lot more confidence. So to an extent I would change a little if my genetic make-up were different. In a sense, genetic make-up is just a competitor to the environmental factors

Twins, share a bond that no parent, child or sibling relationship can ever compare. There are two main types of twins, and these include: monozygotic (identical) twins and dizygotic (fraternal) twins, and they are compared by their emotional, behavioural, and cognitive similarities. (Robert Plomin, 1997). According to Social Issues Referencing, 2007, whereas Identical twins are formed from a single (mono) zygote and are genetic “carbon copies”, fraternal twins develop from two (di) separate zygotes, as a result of two eggs being fertilized by two sperms independently. (Social Issues Referencing, 2007, para. 8)

Both family and twin studies face the problem of ignoring environmental impacts. In family studies, genetically similar members of the same family tend to spend more time together, therefore

Currently a study like it would not be allowed today because many people would disagree to use identical twins for a study because it might affect them. It is going to be hard for the researcher’s to explain to people right now about a study like it. Instead it will be better for the twins to be adopted by the same family or have them be placed in similar environments so they will not feel different from each

Another study strategy to demonstrate the genetic component of a disease, and help to discriminate it from the environmental component is the twin study, which compares the correlation to the disease between monozygotic (MZ), with concordance among dizygotic twins (DZ). This type of epidemiological study 7parte the assumption that twins MZ and DZ suffer similar environmental influence, however, the MZ are genetically identical while the DZ not necessarily presenting genetic identity as similar as two brothers generated at different

In this study, they are used several type of method, one of the technique is used two or more test instrument to ensure the adequate coverage, for example the participants were given a battery of personality and mental ability tests, interest and value inventories and psychomotor tests. In addition, separate of examiners administer the IQ test, life history interview, psychiatric interview and sexual life history interview. The twin also complete questionnaire independently under the constant supervision of the staff members. Twin studies are valuable to researchers because identical twins share 100% of their genes and fraternal twins share, on average, 50% of their genes. Both identical and fraternal twins share certain aspects of their environment (e.g. religious practices in the home). This allows researchers to estimate the heritability of certain traits. Participants are asked about academic ability, personality, and interests; family and social relationships; mental and physical health; physiological measurements. Of interest to researchers are prevalence of psychopathology, substance

Identical twin studies are most useful in determining genetic influence on intelligence. Since the identical twins share the same exact genes, the straightforward comparison of intelligence can display if this human trait is truly heritable. Similarity of intelligence scores between identical twins supports the genetic influence on intelligence. According to Myers (2007),

Women showed a statistically non-significant trend to weaker influence of hereditary effects, while men showed no effect of shared environmental effects. The use of all adult twins in Sweden was designed to address the criticism of volunteer studies, in which a potential bias towards participation by gay twins may influence the

Another study that has been done was with separated twins. Each twin was raised in a completely different environment than the other. Genetically, they were both identical in every way, but the environment that they were raised in was very different. One twin was raised in a very hostile setting and slowly became violent as an adult while the other twin was

When conjoined twins are formed, the female’s egg doesn’t fully split which creates two embryos, their skin and organs can fuse together, but it is very rare. Although the two fetuses will develop

There are two types of twins. One type of twins, called identical twins, is exact clones of each other. They share the same DNA and were made from a single split egg. More research as been done regarding these types of twins as they are the more remarkable kind. Since they are a genetic match, nature plays the

For years I have been fascinated by that mysterious quirk of nature called twins. In my family, there are several sets of identical twins, and I have always concentrated on their similarities. I did not realize that identical twins also have many differences. My identical twin cousins, Sue and Heidi, appear to be perfect mirror images. They love to dress alike. They can feel each other's pain. They sound alike and can complete each other's sentences. But upon taking a closer look, I have found that they are as different as day and night. Aside from Sue and Heidi's outward characteristics, they possess several distinguishing traits that allow them to be viewed as two separate, independent