A new test detecting fetal DNA in a mother?s blood could reduce invasive procedures, such as amniocentesis and removal of tissue from the uterus, to predict birth defects.
In “A Non-invasive Test for Prenatal Diagnosis Based on Fetal DNA Present in Maternal Blood: A Preliminary Study,” published in The Lancet online, Johns Hopkins School of Nursing student Kara Franz and colleagues describe their work isolating fetal DNA to diagnose chromosomal abnormalities.
“Such testing has been hindered by the inability to distinguish fetal DNA from maternal DNA and distinguish the number of fetal chromosomes in the mother?s blood sample,” Franz wrote in the article.
Researchers accurately found trisomy 21, the chromosomal abnormality associated with Down syndrome, in 58 out of 60 cases.
Of the two incorrectly identified samples, one was a false positive and one a false negative. With further refinement, the test could become a useful complement to available prenatal tests, Franz wrote.
