Genetics     

                     

Genetics 

Understanding why people are different  People differ. Some are tall, some are short. Some are loud, some are quiet. Some are happy, some sad. Some do well in school exams, others don’t. Why?  

Understanding why people are different  People differ. Some are tall, some are short. Some are loud, some are quiet. Some are happy, some sad. Some do well in school exams, others don’t. Why?  

A proportion of the differences that we observe between people can be attributed to their genetic differences. At the Hungry Mind Lab, we pioneer the use of DNA-based measures in research to predict people’s developmental differences. We are particularly interested in studying the interplay between genes and environments in children’s cognitive and social-emotional development. 

Children’s early life cognitive development  

In the first years of life, children develop important cognitive skills like language, attention, and memory. These cognitive skills can influence how well children do later in school: those with better language, attention, and memory typically achieve higher school grades. Doing well in school, in turn, predicts many important life outcomes, for example how much someone earns, how healthy they are, and how happy they feel. 

Children’s early life cognitive development  

In the first years of life, children develop important cognitive skills like language, attention, and memory. These cognitive skills can influence how well children do later in school: those with better language, attention, and memory typically achieve higher school grades. Doing well in school, in turn, predicts many important life outcomes, for example how much someone earns, how healthy they are, and how happy they feel. 
Differences in children’s cognitive skills are apparent from as young as 2 years of age, and often increase over time from infancy and throughout childhood. To better understand why children differ so much in cognitive development, we conduct meta-analytic and original empirical studies. Our work on this topic is funded by the Nuffield Foundation and the Jacobs Foundation. Our findings will contribute to developing interventions that improve children’s cognitive skills and in turn reduce the gaps in school performance and educational achievement. 

Our report on the gene-environment interplay in early life cognitive development 

In May 2024, we completed a 4-year long research programme into gene-environment interactions.  
 
We analyzed data from more than 13,000 families and worked with researchers, collaborators, and partners to understand how genetics and environmental factors interact in children’s development during the early years.  
 
Our report summarises our research and explains our findings. Click on the image to access the full report. 

Understanding genetic influences  Differences in our physical and psychological traits, for example our height, weight, and cognitive skills, are partly influenced by the genes that we inherit from our parents. 

The traditional way for studying the influence of genetic inheritance on people’s differences is to compare the resemblance of identical twins, who share 100% of their genes, with that of non-identical twins, who only share 50% of their segregating genes. Such twin study comparisons can help us to estimate the heritability of traits – that is, what proportion of the differences in an observable trait is due to genetic differences. Results from the classic twin design have shown that, on average, genetics can explain 50% of the differences that we observe between people. 
 
Recently, a new approach has emerged to identify the genetic factors or DNA variants that drive the heritability of traits. This approach involves calculating polygenic scores, which aggregate a person’s DNA variants that predict their traits and behaviours. 
 
 
Polygenic scores are based on genome-wide association studies, known as GWAS. GWAS search people’s genomes for DNA variants that are associated with a target trait, for example height or cognitive ability. GWAS have shown that people’s differences in these and similar traits are due to many thousands of DNA variants.  
 
Once we know from a GWAS which DNA variants are associated with a target trait, we can apply this information to any person's genome. That is, we can analyse people’s DNA and see how many of the DNA variants related to the target trait they carry. We can then aggregate these DNA variants to create a polygenic score that indexes the person’s genetic propensity for a trait or behaviour. 
 
In short, polygenic scores can capture a person’s genetic propensity for traits, such as cognitive skills. Because people’s differences in cognitive skills are at least partly heritable, polygenic scores are good predictors of a person’s cognitive skills. 
 
An increasing number of research studies use polygenic scores to predict psychological traits, medical disorders, and psychiatric diagnoses. In our studies, we have used polygenic scores to predict children’s differences in school performance, cognitive ability, and social-emotional development. 
 
We have made a series of videos to explain how genetic influences affect our traits and behaviours.