Background

Evidence implies that there is an association between physical activity and DNA methylation and between methylation and obesity. I will therefore explore the potential mediating relationship of methylation in the relationship between activity and obesity, using epigenome-wide data which have only recently become available on this scale.

Objectives

Primary objectives:

1)Identify methylation variation associated with physical activity and then consider how this variation relates to obesity.

2)Use Mendelian randomisation to investigate causality in any associations between physical activity, differentially methylated regions (DMRs) of the genome, and obesity.

3)Investigate the underlying biological mechanisms that the DMRs may be acting through.

Secondary objective:

1)Explore the relationship between physical activity, DNA methylation variation and cardiovascular health in children.