Week 6 - Future of Behavioral Genetics

Question 1

height historical

Answer 1

smaller between 14th and 18th century

Question 2

height heritability

Answer 2

90%

Question 3

SNP model fitting method

Answer 3

lower CI -> include more genes
heritability first increases
then suddenly drops
the one before is ideal

Question 4

BMI heritability

Answer 4

70%

Question 5

assortative mating physical features

Answer 5

20-30% for height, BMI, waist

Question 6

biological pathways for BMI

Answer 6

gene found in diabetes study

leptin, the hormone for fullness

Question 7

facets of eating behavior

Answer 7

enjoyment
fullness
speed
all highly heritable from early age

Question 8

heritability aging

Answer 8

effect only shows in older cohorts

-> only when people die from natural causes

Question 9

dementia heritability

Answer 9

different for each variant

overall 58%

Question 10

dementia gene

Answer 10

ApoE

removes plaques

Question 11

epigenetic landscape

Answer 11

depending on environment, stem cell takes different irreversible route
then it remembers what it is
daughter generation also

Question 12

DNA methylation

Answer 12

regulates transcription
prohibits transcription factors to attach to DNA
attaches to cytosine bases
CpG sites / island
mechanism of epigenetics
also affects alternative splicing

Question 13

epigenetic mechanisms

Answer 13

methylation
folding of DNA
alternative splicing

Question 14

landmark epigentics study

Answer 14

mothering of rats
unmothered rats had more glucocorticoid receptors in hippocapus
more stress

Question 15

epigenetic example in humans

Answer 15

MAOA gene

promotor enzyme that breaks down monoamines

Question 16

EWAS

Answer 16

epigenome wide association study
mostly about methylation
or histone modification

Question 17

problem of EWAS

Answer 17

epigentics is tissue specific
brain tissue is hard to reach
however, methylation correlates between regions
early child environment changes it in whole body

Question 18

strong epigenetic design

Answer 18

discordant MZ twins
same DNA, C, sex and age
problem: very small sample sizes

Question 19

microbiome skinny people

Answer 19

more Christensenella minuta gut bacteria

Question 20

theory on eating behavior

Answer 20

behavioral susceptibility theory

some have better appetite and lower sensitivity to satiety and therefore overeat

Question 21

fluid vs crystallized

Answer 21

fluid is more heritable

Question 22

heritability multiple-infarct dementia

Answer 22

0%

Question 23

changes in methylation due to smoking

Answer 23

by smoking yourself

intergenerational: your parents
transgenerational: your grandparents

Question 24

purpose of quantitative genetics

Answer 24

genes and environment

Question 25

purpose of molecular genetics

Answer 25

only genes

Question 26

DF extremes analysis

Answer 26

= DeFries-Fulker regression
genetic links between extremes and normal range of variation,
disorders = extremes of normal behavioural dimensions.