Behavioral+Genetics

= = Alyssa Corey, Tricia Hart, Julie Ketcham, Luke Hanson = = =Summary= Behavorial genetics focuses on the study of genetic effects on behavior. In order to determine these genetic effects, researchers typically study traits within family units. These studies, known as family studies, examine how traits vary within the different relationships of the family unit. They do not actually study [|genes]. Instead, they look at genetic relations by looking at related individuals. By looking at shared genetic behaviors between two related individuals, we develop [|concordance] rates which act as predictors of certain genes. These concordance rates tell us how genetically similar any two people are. When a concordance rate is high (ex. identical twins), the likelihood that they will display certain genetic traits is high. By contrast, when a concordance rate is low (ex. two random strangers are studied), the likelihood that they will display similar genetic traits is low. An alternative technique to family studies uses behavioral genetics to study correlations between people of different degrees of relatedness. For example, we confirm that identical twins have the highest concordance rates by first looking at random strangers, then distantly related individuals (second cousins), then more closely related (parent-child), and finally, identical twins. By studying these varied relationships, we can concretely determine genetic effects on behavior. [|Twin studies] are popular in this field of [|developmental psychology]. media type="youtube" key="Trc2dJgeyvc" height="315" width="420" align="center" [|Heritability] plays a role in determining how genes affect behavior. This highlights the effect of environment on personality and behavioral traits by examining shared and non-shared environments. [|Heritability] is determined by the environment and gene x environment interactions. If two related individuals share the same family environment, it is likely that their behavior is shared due to rearing as opposed to two related individuals who occupy a nonshared environment, whose similar genetic traits are most likely determined by their genetic code. This emphasizes the effect of the cultural environment on an individual's behavior and personality traits. = = =Notable Behavioral Geneticists= Notable behavioural geneticists include [|Dorret Boomsma], [|John DeFries], Lindon Eaves, [|David Fulker], John Hewitt, [|Kenneth Kendler], [|John Loehlin], [|Nick Martin], Gerald McClearn, [|Robert Plomin], Theodore Reich, [|Hans van Abeelen], [|Avshalom Caspi], and [|Steven G. Vandenberg], the founding editor of the journal //[|Behavior Genetics]//. = = =Genotype->Environment Theory= Sandra Scarr and Kathleen McCartney developed the [|genotype->environment theory], which says that one's genotype influences which environments one encounters and the type of experiences one has. In other words, genes drive experience. This theory holds that the relationship between genes and environment is reciprocal. In this model, we see various degrees of effects: passive effects, evocative effects, and active effects. Passive effects refer to the effects of the biological parents rearing the child. The word "passive" is used to describe this effect as children are passive recipients of their parents' genes and rearing environment. Evocative effects are the characteristics of children that evoke responses from others. For example, temperament often determines how the child is perceived and treated by others. If a child is happy, light-hearted, and open to love, that child will likely inspire happiness and receive positive attention. If a child is irritable, negative, and doesn't like to be touched, that child is likely to be avoided and receive no attention or negative attention. Active effects are the experiences and environments that a child chooses to experience. Contrary to what one might initially think, this theory proves that siblings become less alike the longer they live together. This occurs because children gain independence and desire to make their own mark in the world.

=Recent Studies= "Twins have a special claim upon our attention; it is, that their history affords means of distinguishing between the effects of tendencies received at birth, and those that were imposed by the special circumstances of their after lives." -- Sir Francis Galton, 19th century behavioral genetics pioneer, //Inquiries into Human Faculty and its Development,//1875


 * While [|Sir Francis Galton] is not a recent researcher in the field of Behavioral Genetics, his ideas have been a favorite tool of recent behavioral geneticists. Twin studies alongside their environmental and genetic backgrounds can be used to study traits from intelligence, to addiction even schizophrenia and depression.
 * Twin studies are very controversial to the public, great gains have been made from studying the lives of twins from neonatal to death. The studies of twins has expanded from one set of twins to multiple sets, extended families longitudinal studies and multiple other variations involving data analysis. The only problem with twin studies is that the variables are always changing the environment of a family is never the same so some data may be skewed due to environmental differences. All of this is essentially going back to the nature vs nurture argument, will we ever know?
 * A look at molecular genetics combined with the traditional twin study will progress the study in the future. DNA holds the key to specifying individual genes that contribute to an overall pattern of heritability.
 * Behavioral genetic methods can be used to test behavioral tendencies that are thought to affect temperamental origins. Twin and adoption studies suggest that individual differences in infant and child temperaments are genetically influenced. The importance of human temperaments go well beyond the nature vs nurture debate. Showing the importance of a non-shared environmental influence and environmental change during development. There are specific links between temperament and behavior problems, showing the power of molecular genetics that identify specific genes that are responsible for the genetic influence on early temperament.



=References= Bjorklund, David F., and Blasi Carlos. Herna%u0301ndez. //Child & Adolescent Development: An Integrated Approach//. Australia: Wadsworth Cengage Learning, 2012. 97-104. Print.

Winerman, Lea. //American Psychological Association :A Second Look at Twin Studies.// April 2004, Vol 35: No.4. Pg 1-4, 2012.

Gega, Stela. //Sir Francis Galton: Biography, Theory, Time Line and References.// May 2000, http://www.muskingum.edu/~psych/psycweb/history/galton.htm. February 13th, 2012.

I've finished the summary and hyperlinked some vocabulary. Tricia, is there any way that you can find some pictures, videos, anything to put in here? Thanks-Alyssa

I Found out how to upload pics so a put two on.... and added a little to my recent studies bullets let me know if you guys like them. --Julie and sense alot of the sources above were linked to wikipedia should we add that to our references ? site it and etc....