B3460 - The power of the environment Environmental mediation of genetic liability - 03/02/2020

B number: 
B3460
Principal applicant name: 
Moritz Herle | Kings College London (UK)
Co-applicants: 
Prof Andrew Pickles, Prof Bianca De Stavola
Title of project: 
The power of the environment: Environmental mediation of genetic liability
Proposal summary: 

The consequences of childhood obesity remain one of the biggest public health burdens in the UK. 1 in 3 children are already overweight or obese by age 10 years. This is especially problematic because obesity has been linked to many health conditions, such as diabetes, cancer and depression. There is now substantive evidence that obesity runs in families, but genetics alone cannot explain the current rise of obesity in the population. So environmental factors have been proposed to be causal for this development. It is this dual determination, that remains paradoxical:
How is it possible that obesity is explained by both genes and environments and what does this complexity mean for public health interventions?
For childhood obesity, we already know that genetic and environmental factors are
important. However, it is not known how environmental factors might be protective of genetic
liability.
The main questions are:
1. Do parental feeding practices, such as offering food to soothe, enhance or buffer the
association between genetic liability and later childhood BMI, and what could be
achieved if we changed parental feeding strategies?
2. Does the child’s physical activity mediate the association between childhood genetic
liability and later BMI, and what would happen if levels of physical activity increased?
3. Can maternal genetic risk influence the child’s body size, even though the genetic liability
are not passed on?
4. What is the association between genetic liability and the built environment of the family
home, such as access to green spaces and public transport?

Impact of research: 
The proposed research is timely, and of great public interest. Polygenic scores for common disease are increasingly available through commercial providers. However, their association with environmental factors is not fully understood. This project brings together methods form genetic epidemiology and mediation analysis, highlighting a novel way to address complex questions, which can be adopted by other health researchers.
Date proposal received: 
Monday, 3 February, 2020
Date proposal approved: 
Monday, 3 February, 2020
Keywords: 
Epidemiology, Obesity, Statistical methods, BMI, Childhood - childcare, childhood adversity, Development, Environment - enviromental exposure, pollution, Genetic epidemiology, Methods - e.g. cross cohort analysis, data mining, mendelian randomisation, etc., Parenting, Physical - activity, fitness, function, Statistical methods