Week 6 - nature vs nurture

Heritability

proportion of variation of traits that can be due to genetics

What is the DRD4 gene?

dopamine receptor gene associated with novelty seeking (extraversion)

DRD4 7R (variant of the gene) = expressed dopamine receptor having less affinity for dopamine binding

people with at least one 7-repeat allele have higher Novelty Seeking than other genotypes

So what is the NT involved in Extraversion?

dopamine

What is the NT involved in neuroticism?

serotonin

A decreased serotoninergic function leads to?

higher neuroticism scores

How does serotonin influence neuroticism?

S transporter gene terminates action of S —> reuptake of S

one or two copies of 5HTT allele (S transporter gene) associated with dec S function = high N scores

What is the genome wide approach (GWAS)?

instead of focusing on one candidate gene you set markers across whole genome and find all variant associated with the phenotype of interest

What is a problem with GWAS?

may miss heritability - GWAS finds some associations but these initially explain <1% variance in personality and lacks replication

Polygenicity

there are multiple genes involved in lot of diff processes that may cause multiple diff traits

What is the epigenome?

secondary layer of biochemical info that modify or mark genome in a way that alters instructions given by the DNA

Epigenetic factors have an impact on gene activation which does what?

influence which genes are turned on and off at diff times and places in body

Epigenome can be altered by?

the enviro

What is transgenerational epigenetic inheritance?

epigenetic changes can be passed from generation to generation

What is the Belsky, Steinberg and Draper hypothesis?

a harsher dev context is predicted to stimulate:

earlier pubertal maturation and initiation of sexual activity

ST and unstable pair bonds

limited parental investment - bear more children but not care for them intensively

What is the Belsky, Steinberg and Draper hyp also known as?

psychosocial acceleration theory

According to Costello 2007, maltreated girls ?? vs non-maltreated girls?

reach pubertal maturity 8 months earlier

What are SNPs?

parts of genes, markers, modifiers

Development systems theory