Week 6 - Future of Behavioral Genetics Flashcards
height historical
smaller between 14th and 18th century
height heritability
90%
SNP model fitting method
lower CI -> include more genes
heritability first increases
then suddenly drops
the one before is ideal
BMI heritability
70%
assortative mating physical features
20-30% for height, BMI, waist
biological pathways for BMI
gene found in diabetes study
leptin, the hormone for fullness
facets of eating behavior
enjoyment
fullness
speed
all highly heritable from early age
heritability aging
effect only shows in older cohorts
-> only when people die from natural causes
dementia heritability
different for each variant
overall 58%
dementia gene
ApoE
removes plaques
epigenetic landscape
depending on environment, stem cell takes different irreversible route
then it remembers what it is
daughter generation also
DNA methylation
regulates transcription prohibits transcription factors to attach to DNA attaches to cytosine bases CpG sites / island mechanism of epigenetics also affects alternative splicing
epigenetic mechanisms
methylation
folding of DNA
alternative splicing
landmark epigentics study
mothering of rats
unmothered rats had more glucocorticoid receptors in hippocapus
more stress
epigenetic example in humans
MAOA gene
promotor enzyme that breaks down monoamines
EWAS
epigenome wide association study
mostly about methylation
or histone modification
problem of EWAS
epigentics is tissue specific
brain tissue is hard to reach
however, methylation correlates between regions
early child environment changes it in whole body
strong epigenetic design
discordant MZ twins
same DNA, C, sex and age
problem: very small sample sizes
microbiome skinny people
more Christensenella minuta gut bacteria
theory on eating behavior
behavioral susceptibility theory
some have better appetite and lower sensitivity to satiety and therefore overeat
fluid vs crystallized
fluid is more heritable
heritability multiple-infarct dementia
0%
changes in methylation due to smoking
by smoking yourself
intergenerational: your parents
transgenerational: your grandparents
purpose of quantitative genetics
genes and environment
purpose of molecular genetics
only genes
DF extremes analysis
= DeFries-Fulker regression
genetic links between extremes and normal range of variation,
disorders = extremes of normal behavioural dimensions.
