Behavioural genetics

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Behavioural genetics is the field of biology that studies the role of genetics in animal behaviour. The field is an overlap of genetics, ethology and psychology (particularly evolutionary psychology). Classically, behavioural geneticists have studied the heritability of behavioural traits.

Francis Galton

In 1869, Francis Galton published the first empirical work in human behavioural genetics, Hereditary Genius. Here, Galton intended to demonstrate that "a man's natural abilities are derived by inheritance, under exactly the same limitations as are the form and physical features of the whole organic world." Like most seminal work, he overstated his conclusions. His was a family study on the inheritance of giftedness and talent. Galton was aware that resemblance among familial relatives can be a function of both shared genes and shared environments. Contemporary behavioural genetics studies special populations—in human research, twins and adoptees and in animal research, specially bred strains and lines—to separate genetic from environmental effects.

The initial impetus behind behavioural genetic research was to demonstrate that there were indeed genetic influences on behaviour. In psychology, this phase lasted for the first half of the 20th century largely because of the overwhelming influence of behaviourism in the field. Later behavioural genetic research focused on quantitative methods, and today there is a large emphasis on applying molecular genetic techniques to isolate individual genes that influence behaviour. Currently, the largest branch of behavioural genetics is psychiatric genetics which studies phenotypes such as schizophrenia, bipolar disorder, and alcoholism.

Recent trends in behavior genetics has indicated an additional focus toward researching the heritability of human characteristics typically studied in developmental psychology. For instance, a major focus in developmental psychology has been to characterize the influence of parenting styles of children. However, in most studies, genes are a confounding variable. Because children share 50% of their genes with each parent, any observed effects of parenting styles could be effects of having many of the same genes as a parent (e.g. harsh aggressive parenting styles have been found to correlate with similar aggressive child characteristics- is it the parenting or the genes?). Thus, behavior genetics research is currently undertaking to distinguish the effects of the family environment from the effects of genes. This branch of behavior genetics research is becoming more closely associated with mainstream developmental psychology and the sub-field of developmental psychopathology as it shifts its focus to the heritability of such factors as emotional self-control, attachment, social functioning, aggressiveness etc..

[edit] Criticism of Behavioural Genetic Methods and Theories

Joseph, J. (2004). The Gene Illusion: Genetic Research in Psychiatry and Psychology Under the Microscope.New York: Algora. (2003 United Kingdom Edition by PCCS Books)
Joseph, J. (2006). The Missing Gene: Psychiatry, Heredity, and the Fruitless Search for Genes.New York: Algora.

[edit] References

Carey, G. (2003) Human Genetics for the Social Sciences. Thousand Oaks, CA: Sage Publications. [1]
DeFries, J. C., McGuffin, P., McClearn, G. E., Plomin, R. (2000) Behavioral Genetics 4th ED. W H Freeman & Co.
Scott, J.P. and Fuller, J.L. (1965) Genetics and the Social Behavior of the Dog. University of Chicago Press.
Weiner, J. (1999) Time, Love, Memory : A Great Biologist and His Quest for the Origins of Behavior. Knopf