HONG KONG, Oct. 3 (UPI) -- A newly identified class of fetal markers found in maternal blood may allow for improved prenatal diagnosis, Chinese researchers reported Monday.
Although low concentrations of fetal DNA have been detected in the blood plasma of pregnant women, the lack of a specific fetal marker to differentiate it from the high levels of maternal DNA has limited its clinical usefulness.
To find a universal marker of fetal DNA, Dennis Lo and colleagues at the Chinese University of Hong Kong searched for epigenetic differences between fetal and maternal DNA.
In a gene called maspin, the researchers found a particular type of chemical modification, methylation, occurs at much higher levels in maternal DNA than fetal DNA.
Unmethylated fetal DNA was detected in maternal blood plasma in all three trimesters, but disappeared within 24 hours of delivery, indicating it is specific to pregnancy.
The scientists said the results may provide the basis for developing non-invasive methods for prenatal diagnosis and fetal monitoring.
The findings appear in the online early edition of the Proceedings of the National Academy of Sciences.
