PSYCH 2AP3 Lecture Notes - Behavioural Genetics, Intellectual Disability, Twin Study
Document Summary
Chapter 9: the inheritance of personality behavioural genetics and. Eugenics: the belief that humanity could be improved through selective breeding. Cloning: the belief that it might be technologically possible to produce a complete duplicate. Modern behavioural geneticists are generally quick to dissociate themselves from these ideas. The real contribution of behavioural genetics is the way it expands out understanding of the sources of personality to include bases in both genes and the environment. Compare similarities in personality between individuals who are and are not genetically related. Concerns the degree to which variation in the phenotype can be attributed to variation in the genotype. Heritability quotient = (rmz rdz) 2. According to twin studies, the average heritability of many traits is about . 40. For most traits the estimates of heritability garnered from nontwin studies are about 20%, or half the average heritability estimated from twin studies. Effects of genes are interactive and multiplicative rather than additive.