The health of children’s bones could be determined before they are born, a new University of Southampton study has shown.
Researchers from the MRC Lifecourse Epidemiology Unit and the Institute of Developmental Sciences at the University of Southampton, as part of the Epigen Global Consortium, looked at whether bone health might be influenced by epigenetic modifications of DNA early in life.
The results, published in the Journal of Bone and Mineral Research, provide an insight into the early determinants of skeletal growth, and improve the understanding of how osteoporosis could be prevented in future generations.
There is growing evidence that whether genes are expressed or not in particular human cells can change throughout life and can be affected by a range of environmental factors even before birth, such as their parents’ health, diet and lifestyle before and during pregnancy. This switching on or off of genes is known as “epigenetic modification” and an important epigenetic mechanism is DNA methylation.
The researchers analysed the levels of DNA methylation in umbilical cord tissue of 669 babies born in the Southampton Women’s Survey. They compared the DNA methylation levels in the CDKN2A gene to the bone mass of the child at four and six years of age, measured using DXA bone densitometry. They found that higher DNA methylation in particular parts of the CDKN2A gene, which plays a role in development and ageing, was associated with lower bone mass at four and six years.
Analysis showed that a 10 per cent increase in methylation was associated with a decrease in total bone mass of around 4–9g at age four years. Further laboratory analysis showed that methylation of the CDKN2A region is important for the function and survival of bone cells.
Nicholas Harvey, Professor of Rheumatology and Clinical Epidemiology at the University of Southampton, led the study with Elizabeth Curtis, Wellcome Trust Clinical Research Fellow, and Robert Murray, Postdoctoral Research Fellow.
He said: “The health of a child’s bone when they are young can influence the risk of osteoporosis in older age. This study provides exciting insights into the role of epigenetics in bone health, and might allow us to more accurately predict an individual’s future risk of osteoporosis. Our ongoing studies should enable us to work out whether interventions during pregnancy, for example vitamin D supplementation, will alter the epigenetic marks, and lead to improved bone health.”
Source: University of Southampton