Session 4 Flashcards
Behavioural genetics
Field concerned with how genes and the environment INTERACT to influence individual behaviour
Epigenetics
Study of heritable changes in gene expression that doesn’t involve changes to underlying dna sequence
Sometimes things in our environment can cause a gene to turn on or off
Behavioural genomics
Study of multiple genes and numerous environmental factors that influence behaviour
VERY often it’s not a single gene that causes a trait or disorder
Evolutionary psychology
How our thoughts, feelings, behaviours have been shaped by evolutionary forces
Eugenics
Selective breeding of humans
How do you ethically study nature nurture in humans
Study family members with different degrees of genetic relatedness
Identical twins vs siblings vs adopted siblings
Quantitative genetics
Scientific discipline in which similarities among individuals are analyzed based on how biologically related they are
We assign a quantitative value to those similarities
Heritability coefficient
A number between 0-1 that speaks to how much something is influenced by genetic factors
Everything partially inherited
3 problems with heritability quotient
1- if environmental requirements are all met, we over estimate the effect of genes
2-heritability coefficients are measures of variability of dependent factors and they do terrible traits with little variability
3- heritability coefficient doesn’t take into account interaction
What’s a gene
Segments of dna
Basic biological unit that transmits characteristics from one generation to the next
How many genes in a human cell
25000
Types of nucleotide (staircases in the double helix)
Adenine
Guanine
Cytosine
Thymine
How many genes do humans share
99.9% define what we are as a species
The 0.1% makes us different
What is personality in terms of genes
Traits that are stable in the individual but vary in the population
5 factor model
-openness
-conscientiousness
-extraversion/introversion
-agreeableness
-neuroticism
Natural selection
A good memory to remember the plant that made me sick
Fast legs to run from tiger
Sexual selection
What makes me attractive to a mate so my genes are passed on
Parental investment
Women and men
Women- need to be more careful to pick their partners cus the minimal investment is greater (pregnancy)
Men- minimal investment is just sex. Not that picky
Phenotype
Observable characteristics
Genotype
Organisms complete genetic material
Epigenetics
Study of differences in gene expression without changes to dna structure
Epigenetics
Study of differences in gene expression without changes to dna structure
What does it mean when a gene is “turned off”
No longer providing information to make certain proteins
How do genes change without changing the dna
Adding a chemical (methyl group) to some of the nucleotides
Sequence is the same. Just a chemical is added
Histone
Adding a chemical to the binding that helps wind the string of the dna
Histone and depression
Ppl with depression had histone markers that suggested less gene expression involved in emotional regulation
Methylation
A methyl group added to genes
How do antidepressants work
Increased histone markers on increased gene expression
Reversed gene expression induced by defeat stress
