Researchers from the University of Southampton and King's College London investigated the relationship between DNA methylation in infants and the mother's blood glucose levels. The study, published in PloS Medicine, found that infants who were exposed to maternal gestational diabetes mellitus (GDM) had chemical changes that affected their DNA. However, these changes appeared to be reduced by lifestyle interventions during pregnancy.
'These findings suggest that improvements to diet and physical activity can have an impact on the development of their children,' said study author Professor Karen Lillycrop, professor of epigenetics at the University of Southampton.
The scientists used samples from over 500 infants that were collected in a separate UK wide trial of lifestyle intervention in pregnant women with obesity (UK Pregnancies Better Eating and Activity Trial – UPBEAT). After analysing these, they concluded that high glucose levels in mothers who developed GDM were linked to epigenetic modifications in infant DNA.
In GDM, a hormone produced by the placenta prevents the body from using insulin effectively and so glucose builds up in the blood. These high levels of glucose in mothers with GDM may trigger chemical changes to a baby's DNA during development.
The study also showed that through interventions designed to improve the mothers' glucose levels – by addressing their diet and physical activity – the impact on the infant associated with maternal GDM exposure can be reduced.
'We have known for some time that children of mothers who had gestational diabetes are a greater risk of obesity and poor control of glucose; this new research implies that epigenetic pathways could be involved,' said Professor Lucilla Poston, who led the UPBEAT trial at King's College London.
Discussing the implications of this work, Professor Lillycrop said that further studies are needed to establish whether the healthy lifestyle changes during pregnancy, and associated reduction in impact on infant DNA 'are accompanied by improved health outcomes for the children in later life.'