Cell-free DNA methylation profiling may support the presymptomatic assessment of preeclampsia (PE) risk, according to a paper published on August 28 in Nature Medicine.
Preeclampsia is a complication that affects around one in 25 pregnancies. Women with PE experience severe new-onset high blood pressure and high levels of protein in their urine in the second half of their pregnancies. Currently, the only treatment is to induce delivery of the baby, which, in the case of early-onset PE, results in premature birth and associated health risks for the mother and child.
Administering low-dose aspirin before 16 weeks of gestation can prevent the complication and is particularly effective at stopping early-onset PE, but physicians lack a screening test that can simply and reliably identify at-risk women before they develop symptoms.
Researchers in Belgium have identified changes in DNA methylation as a way to predict PE. The team uncovered the changes by profiling the methylomes of plasma-derived cell-free DNA from 498 pregnant women, around one-third of whom developed early-onset PE. The discovery of the changes in DNA methylation informed the development of a model for predicting PE risk.
In the validation section of the study, the researchers combined the PE model with existing clinical and demographic risk factors to predict the likelihood of a person developing the complication. The screening approach predicted 72% of people with early-onset PE at 80% specificity.
The researchers developed their panel using next-generation sequencing equipment from Illumina but said they see potential to transfer the test to other genomic analysis platforms. If commercialized, the assay could be performed alongside another cell-free DNA assessment that checks for evidence of Down syndrome, Edwards syndrome, and Patau syndrome (trisomies 21, 18, and 13, respectively) between 10 and 14 weeks of pregnancy.
