Class Notes (834,049)
Canada (508,296)
Criminology (466)
CC210 (30)


4 Pages
Unlock Document

Jennifer Lavoie

Psychology of Crime September 26 , 2012 Week 3, Wednesday Role of genetics on crime: Lombroso: Anthropological criminology: • criminality was inherited • savage • resemble primate in appearance and behaviour • Born criminal had physical defects • as well as in the way the walk, looked and behaved. Sloping and protruding foreheads, unusual ear size, lower jaw is protruding from the face, symmetry is not present between left and right sides, longer arms. Lombroso was the first to say that criminality is a genetic trait. Estimating Influence of Heritability family studies, twin studies and adoption studies. Criminal Families: Juke family study: By richard L dugdale: An investigation of the hereditary line of a family in New York (709 family members) 140 criminals/offenders. 60 habitual thieves, 7 murderers, 50 prostitutes. Concluded genetics, shared environment played role. Problem with the study: not all the 709 family members were related by blood. They were married in etc. Twin Studies: Dizygotic Twins: fraternal- two different eggs, only case where you can have a girl and boy. Genetically as different as non-twin siblings. Monozygotic: Identical twins Same egg- split it two. Share same genes, DNA. Concordance Rate: Degree to which related pairs of subjects demonstrate a particular behaviour or condition. • % rate • What's the percent of twins that both engage in crime, or both do not engage in crime. Monozygotic vs. Dizygotic: If genes influence crime, identical twins should have a higer concordance rate for having a criminal history that fraternal twins. B/C MZ twins share more genetic make-up. Twin Studies: Lange 1929 Twin Study: Compared criminality of MZ and DZ twins. MZ = 77% criminality (13 pairs) DZ = 12% criminality (17 pairs) Christiansen: 1977 MZ = 55% similarity (339 pairs) DZ = 17% (426 pairs) Twin studies: Effect of environment Shared envionments: • Prenatal, family, home. • Affects twins in the same way, makes twins more similar. • Influences often decrease as child grows. Non shared environments: • Interests, activities, friendships. • Makes twins dissimilar • Influences often increase with age. Confound: Identical twins may be more similar in criminality because they shared the same environments (growing up, prenatal, home etc) Example: FASD, crime models Was it the shared environment? Or was it the genes that makes the rate so high with identical twins? Adoption Studies: Deals with shared environment confound. Compare concordance rates of: • Children and their biological parents vs. • Children with their adoptive parents. Higher concordance rates between biological parents, and their adopted-away children indicates a genetic influence on the trait/behaviour. (biological parents have
More Less

Related notes for CC210

Log In


Join OneClass

Access over 10 million pages of study
documents for 1.3 million courses.

Sign up

Join to view


By registering, I agree to the Terms and Privacy Policies
Already have an account?
Just a few more details

So we can recommend you notes for your school.

Reset Password

Please enter below the email address you registered with and we will send you a link to reset your password.

Add your courses

Get notes from the top students in your class.