During pregnancy, the placenta leaks fetal cell-free DNA into the maternal bloodstream. As a result, a maternal blood sample contains a mixture of fetal and maternal circulating DNA. The Sage prenatal screen directly measures the amount of this cell-free DNA and can detect small changes in the DNA ratio between the maternal and cell-free DNA to estimate the risk of a fetal chromosomal aneuploidy or a microdeletion being present. The Sage prenatal screen employs the latest advances in Next Generation (NGS) to analyse the DNA.
The Sage prenatal screen workflow:
The Sage prenatal screen is a simple, fast process that can be run by any trained technician. It is suitable for low to medium volume sample throughput laboratories, enabling local clinical laboratories to meet and grow with their rising demands. The Sage workflow runs on the Ion Torrent sequencing system from Thermo Fisher. For laboratories requiring full automation, there are options available in some territories with our other NIPT solution – the IONA® test
Cloud-based NIPT analysisThe Sage analysis uses Sage Link which is a cloud-based bioinformatics portal. The resulting data is processed so that a small data file can be easily, quickly and safely uploaded to Sage Link. After a brief time, individual patient reports are ready for download. Each report is easy to follow and is signed by the laboratory once it is finalised.
The Sage prenatal screen analyses and reports the amount of placental cfDNA circulating in the maternal blood stream and reports this as fetal fraction. Some pregnant women may have too little fetal (placental) DNA available for analysis which is reported as "low fetal fraction". There may be several reasons for this; for instance, women with a high maternal weight may have increased blood volume which could result in a dilution of the cell-free placental DNA in the maternal plasma.
The Sage prenatal screen incorporates clever bioinformatics software that is able to produce valid and accurate results in samples that have as little as 3.5% fetal fraction.