Nature vs nurture

Question 1

What is gene-environment correlation?

Answer 1

People select, modify, construct and re-construct their experiences in part on the basis of their genetic propensities

Question 2

What are the 3 types of G-E correlation?
Who proposed them?

Answer 2

1. Passive
2. Active
3. Evocative

Plomin et al 1977

Question 3

What is passive G-E correlation?

Answer 3

Parents provide genes and early environments

Question 4

What is active G-E correlation?

Answer 4

Tendency for people to actively seek out environments that reinforce their genotypic dispositions

Question 5

What is evocative G-E correlation?

Answer 5

Elicitation of environmental responses by genetically influenced behavior’s

(because of generically influence behaviors I evoke responses from the env)

Question 6

What is a G-E interaction?

Answer 6

The possibility that pre-existing genetic propensities make individuals exposed to certain environments more likely to develop a disorder than those without such a genetic vulnerability

Can be explaining why not all kids with CT history develop psychosis

Question 7

What is a Poligenic Risk Score (PRS)

Answer 7

It is a single genetic measure representing the risk carried by genes of a person

For each person you calculate weight sum of all risk alleles in their whole genome

They allow exploration of the genetic associations in the whole genome instead of single gene (Caspi et al., 2003)

Question 8

Issues with G-E studies

Answer 8

1. Which study design convenience or random sampling?
2. Which effect is measures G or E?
3. How is G/E measured?
4. Need for v large samples to power gene studies
5. Can you replicated the finding?
6. How ethnically generalizable are the findings? How about age groups?

Generally: it is very likely that we are measuring the effects of many genes on many environmental factors