genetics Flashcards
(39 cards)
behav genetics
understanding the influence of genetics on expression of characteristics and behaviours → what is inheritable? (twin and adoption studies)
molecular genetics
which genes are involved in behaviour → what genes are involved in heritable behav?
evolutionary psych?
understand how natural selection shapes psychology
determinism
-biological traits that lead to behav cannot be changed
-A person with biological determinism lacks free will and cannot be treated
*CRIMINAL BEHAVIOUR not under genetic control
phrenology
-franz gall
-Believed there was a relationship between a person’s mental attributes and the shapes and size of their skull
-Can predict behaviour and personality from physical features
-Heavily criticized, but legacy remained
atravism
-cesare lombroso
-Possession of physical features (some environmental) more common in criminals
-Known as atravism and they indicated bearer was an evolutionary throwback
-Those with them should be preemptively punished
-Seen as primitive and lesser
-Argued that biology cannot be changed
eugenics
Francis Galton
-Anything including poverty or crime was heritable due to the discussion of Darwin’s theory
-Apply reproductive control over ‘lower classes’ and the higher ups should have bigger families (positive eugenics)
-Led to WW11 genocides and sterilization of many people
-Misunderstood science..criminal behaviour cannot be fully explained using just biology
jukes family
-Late 19-early 20th century
-Sociologist Dugdale visited jails in New York
-Found blood relatives of Jukes family with half having convictions of criminal behaviour
-Attributed criminality to environment more than genetics
-Advocated for improving conditions for the poor
-Mix of environment AND genetics to fully explain criminal behaviour
twin studies (+ summary)
-Monozygotic: identical twins (MZ)
–> Split of egg but only 1 sperm, same sex
-Dizygotic: fraternal twins (DZ)
–> 2 eggs and 2 sperms
-MZ twins have a higher concordance rate for criminality → meta-analysis
-Avr 51.5% for MZ twins and 20.6% for DZ twins
-Proves there is a genetic component to criminal behav
concordance
-Degree to which pairs of people both show a particular behav or condition
-Percent that 2 twins match each other
-If 1 twin has a history of crim behav, 60% chance of the other twin having a history of criminal behaviour
problems w/ twin studies
-Sample size/sample bias
-Determination of zygosity
-Political influence/bias
-Racial bias
-Only looked at male twins
-Assumption of similar environments → possibly for MZ twins
-Homogenous populations may not be applicable elsewhere
-Ethics of those raised apart
adoption studies
-Separate genetics from environment
-heredity= biological, environment= adoptive
-Criminal convictions more common with adoptees with criminal BIOLOGICAL parent
-20% effect of heredity only while 13.5% no effects of heredity or environment
-24.5% effects of heredity and environment, 14.7% effect of environment only
-Nature + nurture
problems w/ adoption studies
-less common than twin studies
-adoption parents are screened for good environment
-Assumption of adoption immediately after birth (no relation with biological parent)
-Ethics of those raised apart
heritability studies
ROLE of genetics
molecular genetics
WHAT genes are involved + HOW MANY
MAOA gene
-MAOA-L (low-activity variant) → warrior gene because its relationship with aggression
-MAOA-H (high activity variant)
MAO enzymes
-Breaks down neurotransmitters
-Sex linked
gene x environment interactions (childhood abuse)
-Interactions of genetics and environment is a predisposition (risk factor), not a determinant
-CA + MAOA variant (low) = antisocial behav
-CA + MAOA (high) = no antisocial behav
-No CA + MAOA (low) = no antisocial behav
XYY male
-Extra Y chromosome
-0.1% in general population + 1.9% in violent criminal population
-No actual association with violence, just tall stature, acne, and slight intellectual disability
-Aggression from genetics or environment?
-Environment has a larger role on how a person turns out
Diathesis-stress model
-Diathesis: genetic vulnerability or predisposition to develop certain psychopathological condition (risk factor)
-Risky genotype + negative environment =adverse outcome
-Risky genotype + positive environ =neutral/positive outcome
Differential Susceptibility model
-Genotype plasticity
-INDIVIDUAL SUSCEPTIBILITY
-Examines susceptibility to environmental effects
epigenetics
-Processes that change gene expression, without altering genetic code
-Maternal stress during pregnancy can affect the offspring’s behaviour
-Not that researched on behaviour more researched on disease
-As environment changes, it affects the genes we express
natural selection
-Enhance reproduction and survival of species
-Process that drives adaptation
evolution of selfishness
acting in a way that increases the chance of your own survival success at the cost of someone else’s
