Six key genes have been identified in the largest study of premature birth to date.
The findings, yielded from a genome-wide association study of around 50,000 women, could potentially lead to predictive testing for premature birth and early preventative intervention.
'Previous research has suggested that about 30 to 40 percent of the risk for preterm birth is linked to genetic factors,' said co-lead author Dr Louis Muglia, co-director of Cincinnati Children's Hospital Medical Centre. 'This new study is the first to provide robust information as to what some of those genetic factors actually are.'
Premature birth is the leading cause of death in children under five, yet research is complicated by the interactions between the fetal and maternal genomes, which determine the likelihood of such an event occurring.
The researchers used data obtained through 23andMe to compare the genetics of mothers and infants against birth data. They found the most significantly associated genes were in the maternal genotype. These included EEFSEC, a gene involved in cellular functions involving the mineral selenium, found in meat, greens and some nuts. The authors suggested there could be a correlation between reduced selenium levels in the mother and an increased risk of premature birth, especially as Malawi, the country with the highest prevalence of selenium deficiency, also has the highest occurrence of premature birth worldwide.
Another highly correlated gene, WNT4 is vital to prepare the uterine lining for pregnancy by augmenting oestrogen signalling. This finding suggests uterine cells could be targeted for further investigation into premature birth.
Other genes linked to premature birth had roles involving immune development, blood pressure control and uteroplacental circulation.
The research, however, only analysed the genomes of women from European descent, so the findings cannot be directly extrapolated to reflect the genetics of other ethnicities, but they provide insight of what type of genes play a role in premature birth.
'These are exciting findings that could play a key role in reducing newborn deaths and giving every child the chance to grow up smart and strong,' said Trevor Mundel, President of the Global Health Division of the Bill & Melinda Gates Foundation, one of the funders of the study.
'Not only did the study reveal several genes linked to pre-term birth, it also identified a simple, low-cost solution – selenium supplements for expectant mothers – that, if confirmed, could save thousands of lives. It's a great example of the power of public-private partnership,' Mundel added.
The study was published in the New England Journal of Medicine.