Exploring Gene-Behavior Relationships Flashcards
Sapolsky, Robinson(1), Holden
One example of gene regulation of behavior is ____ disease, a neurodegenerative disease that affects cognition and communication abilities
Huntington’s
Huntington’s disease results in increased ____ repeats in chromosome ____ of the HD gene that results in a ____ protein sequence.
CAG; 4; longer
On a G x E graph, what does it mean if two lines overlap with no slope?
No variation in genetic expression regardless of the environment
On a G x E graph, what does it mean if two lines overlap with a slope?
Only environmental variation, no genetic variation
On a G x E graph, what does it mean if there’s two lines parallel lines with no slope?
Only genotypic varation, no environmental effects
On a G x E graph, what does it mean if there’s two lines parallel lines with a
slope?
Both genotypic and environmental variation, although without an interaction
On a G x E graph, what does it mean if the lines cross each other?
GxE interaction: Environment effect occurs in both genotypes in opposite directions
On a G x E graph, what does it mean if one line is flat and the other has a slope?
GxE interaction: Environmental effect only occurs with the one that has a slope
Normal variation in human behavior mentioned in Holden perspective piece are ____ ____ (AVPR1a allele –> used to test relationship compatibility), ____ and ____ emotions, ____ , and ____ seeking behavior (Dopamine D2 receptor)
pair bonding; anxiety; negative; aggression; novelty
Holden Perspective Piece
SERT – short allele have ____ serotonin in synapses and are on average more ____, and are ____ likely to experience major depression after stressful events, but no differences in depression for people with different SERT alleles if no major stressful events. Variation explains 4% variation in behavior
more; anxious; more
Holden Perspective Piece
Low activity MAO-A alleles lead to more of ____, and stronger association if exposed to child abuse, which is a form of ____x____ ____
aggression; gene x environment interaction
Human gene-behavior studies show that, while ____ can affect ____, the most “potent” single ____ are only explaining <____% of variation in a normal trait, with many ____x____ ____ going on. Studies also fail to replicate
gene; behavior; gene; 5; gene x environment interaction
Sapolsky Piece: A Gene For Nothing
- Although all members of a species are considered to be exposed to the same environment, specific pattern of ____ varies a lot, such as the ____ and ____ of events, and whether events coincide with major ____ changes of the ____
experience; timing; spacing; developmental; brain
Sapolsky Piece: A Gene For Nothing
- The assumptions of gene worshipers include
1/ seeing ____ as the commander and ____ directly code for ____, even minute-to-minute behavioral decisions
2/ The body must obey ____ commands
3/ ____ cannot be resisted through conscious choice
4/ there is no room for ____ influence
DNA; genes; phenotypes; DNA’s; genes; environmental
Genes are involved in coding for ____, which affects behavioral ____, ____, and ____, but they do not result in behavioral ____
proteins; sensitivities; tendencies; responsiveness; inevitabilities
Distinguish between the commander perspective and the servant perspective of genes
“Commander”: genes are blueprints for behavior
“Servant”: genes are used by the environment to influence behavior in response to it
Sapolsky Piece: A Gene For Nothing
- What are “two startling facts” that complicate the idea of a gene “for” a behavior?
- Most DNA is non-coding (regulatory)
- This non-coding DNA actually varies more between individuals than the coding DNA
What is a model organism?
Originally proposed as animal models for human behavior that are easy to work with, has short reproductive cycle, and amenable to genetic manipulations
Popular model organisms for social behavior + genetics
- Song birds
- Cichlid fish
- Honey bees
- Voles
- And almost anything (with some limitations)
Physiological time scale of behaviors
- Minute to minute
- neurons firing, hormones being released
Developmental time scale of behaviors
- Over a lifetime
- Brains develop, organs become active and inactive
Evolutionary time scale of behaviors
- Many generations
- Genes vary and are naturally selected to shape adaptive behavior
