- Low levels of DLK1 blood marker help predict poor fetal growth
- DLK1 protein is found in increased amounts in the mother's blood during pregnancy
- New finding could aid decisions on early elective deliveries
Expectant mothers could soon be given a blood test to detect small babies at stillbirth risk
1 in 20 babies are starved in the womb due to placental malfunction or poor blood flow through the umbilical cord. These small babies are at risk of dying or left with cerebral palsy.
‘Low levels of the blood marker known as DLK1 are a good predictor of poor foetal growth and complications of pregnancy, and could be used as a non-invasive prenatal diagnostic test.’
The risks associated with the tiny babies are not detected in low risk healthy mothers.
Queen Mary University scientists have discovered the presence of DLK1 protein in the blood of expectant mothers which could be used to develop tests to determine the health of their babies and aid decisions on early elective deliveries.
The study initially used mice experiments that involved knocking out the gene in either the foetus or the mother, and then measuring the mother's DLK1 level to determine its source. The protein originated from the embryo. This means that the levels of the protein in maternal blood could provide a direct readout of the embryo's biological state.
The team further analyzed how DLK1 affects a pregnant mouse's metabolism. When DLK1 was inactivated in pregnant mice, their fasting response was impaired by not being able to begin ketosis. This indicated the importance of DLK1 in providing energy for the foetus and their growth, and DLK1 levels in the mother were found to be a good predictor of the mass of their offspring.
Finally the research team studied 129 first time mothers, taking measurements of DLK1 levels in their blood and recording the outcomes of their pregnancies. They identified that low DLK1 levels were associated with reduced growth of the foetus resulting from pregnancy complications, including poor blood flow through the umbilical cord.
Lead researcher Dr Marika Charalambous from QMUL said: "At the moment, there are very few ways of predicting which pregnancies will go wrong, and which small babies are small because they are not getting enough nutrition while in the womb, and which are small simply because of their genes."
"It's incredibly important to start developing tests that can give an obstetrician much more information on the pregnancy before delivery, so that they can intervene before complications come to crisis point.
"Measuring DLK1 levels in the mother's blood could be a reliable and non-invasive way of predicting whether there are likely to be complications, especially those that cause reduced nutrient supply to the baby. In those instances, you really need to get the baby out quickly, so women could opt to have an early elective delivery." DLK 1 Protein
Protein delta homolog 1 (DLK1) is a protein encoded by DLK1 gene. The protein is found in high levels in the mother's blood during pregnancy, in humans and rodents.
Very few research has been conducted so far detailing on the significance of the DLK1 protein.
Further clinical studies in humans are required to fully determine DLK1's potential as a prenatal diagnostic.
The study funded by the Centre for Trophoblast Research at the University of Cambridge and the Medical Research Council, published in Nature Genetics.