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How genetics shapes what welearn

Professor Robert Plomin,Institute of Psychiatry, Psychology andNeuroscience

Resilience

How heritable is…

0% heritable 100% heritable

0% heritable 100% heritable

0% heritable 100% heritable

Eye colour

Weight (BMI)

School achievement (GCSE)

50% heritable

Estimating heritability

Identical twins(monozygotic, MZ)

Fraternal twins(dizygotic, DZ)

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0102030405060708090

100

Achievementat 7

Achievementat 9

Achievementat 12

Achievementat 16

Achievementat 18

Her

ita

bili

ty(%

)

Test of Word Reading Efficiency(fluency and phonics) at age 7*

40 words 40 non-words

~ 70% heritabilityfor both wordsand non-words

*Very similar to UKPhonics Screening Check (Year 1)

Kovas … Plomin (2007)SRCD Monographs

Meta-analysis of 2800 reports of 5000 traitsin 2.6 million twin pairs

(Polderman et al Nature Genetics 2015)

0102030405060708090

100

Physical Physiological Psychological

Her

ita

bili

ty(%

)

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A GC

TG

TT

AC

C C CG

GA

AT

TTC G G

GC

AA

AT TC G

TC

CA

AG

G G T

A TAdenine Thymine C Cytosine G Guanine

A GC

TG

TT

AC

C C CG

GA

AT

TTC G G

GC

AA

AT T G

TC

CA

AG

G G T

T

Single Nucleotide Polymorphism(SNP)

C C CT T T

3 Genotypes

2 AllelesTC

Finding DNA differences responsible for theheritability of traits

Get DNA GenotypeSNPs

Correlate SNPswith traits

Genome-wide association(GWA)

Single nucleotidepolymorphism (SNP)

Genome-wide polygenic scores

Many polygenic scores of psychological traitsare already available

02468

1012141618202224

Schizophrenia Bipolardepression

Majordepressive

disorder

Educationalachievement

Intelligence Readingability

Va

ria

nce

exp

lain

ed(%

)

Mental illnesses Mental abilities

10

2015

50

7%10%

15%

2%3%

10%

Resilience

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Get my DNAGenotypemy SNPs

Create my polygenicscores and compare

Where are mypolygenic scores?

Distribution of height

My height196 cm

(99th percentile)

Num

bero

find

ivid

uals

My phenotypic height

Polygenic scores for height in population

90th percentile

Num

bero

find

ivid

uals

My polygenic score for height

50%

2%

98%

50%0% 2% 98%Height polygenic score

Heig

htpe

rcen

tiles

me

Height by deciles of polygenic score

75th percentile of height

25th percentile of height

Hei

ghtP

erce

ntile

s

Deciles for Height Polygenic Score Distribution of weight

My BMI = 30 (114 kg)70th percentile

Num

bero

find

ivid

uals

My body mass index (BMI)

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Polygenic scores for BMI in population

My polygenic score94th percentileN

umbe

rofi

ndiv

idua

ls

My polygenic score for BMI

My BMI70th percentile

Polygenic scores in population

Schizophrenia(85%)

Num

bero

find

ivid

uals

Educationalachievement

(94%)

Bipolardisorder

(22%) Alzheimerdisease

(39%)

Major depressivedisorder

(33%)

Alzheimerdisease?

My polygenic scores for psychological traits

DNA.Land

Smith, D. J., Escott-Price, V., Davies, G., Bailey, M. E., Colodro-Conde, L., Ward, J.,... & Hagenaars, S. P. (2016). Genome-wide analysis of over 106 000 individualsidentifies 9 neuroticism-associated loci. Molecular psychiatry, 21, 749–757.

DNA.Land Research implications of polygenic scores: Novel topics

▲Achievement differences between selective and non-selectiveschools

Smith-Woolley …von Stumm … Plomin (2018)Science of Learning

Emily Smith-Woolley

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▲Symptoms▲Qualitative diagnosis

Impact of polygenic scores on clinical psychology

Before After▲Causes▲Quantitative dimensions

Polygenic scores are normally distributed

Polygenic scores

Num

bero

find

ivid

uals

There are no common disorders,just quantitative traits

Polygenic scores

Commondisorders

Plomin et al (2009). Common disorders are common traits.Nature Reviews Genetics.

Num

bero

find

ivid

uals

▲Symptoms▲Qualitative diagnosis▲Cures▲One-size-fits-all treatments

▲Negative genomics

Impact of polygenic scores on clinical psychology

Before After▲Causes▲Quantitative dimensions▲Prediction and prevention▲Individually tailored

interventions▲Positive genomics

From negative to positive genomics

Polygenic scores

Commondisorders??

• Promise• Strength• Ability• Resilience

• Problem• Weakness• Disability• Vulnerability

Genetics and education:implications

What follows if we accept the evidence for the importance ofgenetics?

Genetics: the elephant in the classroom

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No necessary policy implications

▲ Policy depends on values as well as knowledge

▲ Better decisions with knowledge than without (evidence-basededucation)

Genetics and education: implications

Do we stop teaching children?No! ‘Heritable’ does not mean ‘innate’

-- Children have to be taught to read

‘Heritable’ does not mean ‘immutable’-- Probabilistic propensities-- ‘What is’ not ‘what could be’

Genetics and education: implications

Justify social inequality? Educate the best, forget the rest?

▲ No! The essence of democracy is that people are treated equallydespite their differences

Genetics and education: implicationsDemocratic values and genetics

n Equality of educational opportunityn Social mobilityn Maximise potentialn Personalised learning

All will increase heritability!

Heritability is an index of equality of educational opportunity.

A genetic way of thinking about education

n Recognition of and respect for individual differencesn Education is not just a curriculum imposed on studentsn Students select, modify and create their experiences in part

based on genetic propensities

Passive model ofimposed environments

(instruction)

Active model ofshaped environments

(education)

Choice, opportunities, personalised learning

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How genetics shapes what welearn

Professor Robert Plomin,Institute of Psychiatry, Psychology andNeuroscience