In prenatal trisomy testing: what is cell-free DNA testing?
Cell-free DNA fragments are short fragments of DNA found in the blood. During pregnancy, there are cell-free DNA fragments from both the mother and fetus in maternal circulation. It is possible to analyze cell-free DNA to detect common fetal trisomies such as Down syndrome (trisomy 21). Cell-free DNA is sometimes abbreviated and referred to as “cfDNA” in the literature.
Ariosa Diagnostics has developed advanced DNA analysis technology capable of precisely identifying and counting cell-free DNA fragments in maternal blood. By analyzing maternal blood for cell-free DNA fragments from a potentially aneuploid (trisomy) chromosome, and comparing the results to what would be expected from that of a euploid chromosome, Ariosa has developed a directed DNA analysis approach that can determine with enhanced sensitivity and specificity whether a fetal trisomy may be present.