Scientists to investigate cause of heart defects in children

12 March 2018        

Category: Research

Scientists at the University of Oxford will try to identify new reasons why children are born with heart defects. 

Protein Sparrow 640

To develop properly, heart stem cells need the presence of protein (shown in green) to keep dividing. Environmental factors, like a lack of oxygen or iron, can reduce the amount of protein (right) and stop heart stem cells dividing. This lack of new cells results in a type of heart defects commonly called a “hole in the heart”.

Dr Duncan Sparrow has been awarded £941,000 by the BHF to set up a research team to determine how environmental factors can cause abnormalities in how the heart develops. 

Congenital heart disease (CHD) is a heart condition or defect that develops in the womb before a baby is born. In the UK, heart defects are diagnosed in around 4,000 babies each year - the equivalent of 12 babies each day - with more diagnoses later in life. Estimates suggest that as many as 1-2 per cent of the population may be affected.

Heart defects can occur as a result of faulty genes inherited from the parents. They can also be caused by environmental factors in the womb, such as if the mother is taking certain medications while pregnant. However, the biological processes by which these environmental factors lead to CHD are not known. 

Environmental factors

In previous research Dr Sparrow has shown, in mice, that low oxygen levels in the womb can lead to heart defects in the developing in the offspring. After investigating the reasons, he discovered that a normal biological response to low oxygen – known as unfolded protein response or UPR – interferes with the production of stem cells that form the developing heart. He believes that the UPR might be triggered by other environmental factors, such as low iron levels, and will now investigate this in mice. 

Dr Duncan Sparrow said: “CHD is the most common human birth defect. It is a major cause of infant death and ill health, and requires ongoing medical treatment throughout life. 

“In this study we’ll seek to establish if the problems in the development of the heart result from the response of the UPR mechanism to environmental factors. 

“This could help us identify factors that raise the risk of heart defects and ultimately shape advice given to women who are planning a pregnancy.” 

Improving treatment

Dr Noel Faherty, Senior Research Advisor at the BHF said: “We have known for decades that environmental factors can affect the proper formation of the infant heart, but we know very little about the mechanics of how this occurs.  

“This project will provide us with new insight as to why so many children are born every year with a heart problem. 

“Research like this is the foundation on which improvements in the prevention and treatment of heart conditions are built. It’s only thanks to the generosity of the public that we can fund the science that offers to opportunity to save and improve lives.”