Sequenom Still Very Good, Just No Longer Perfect

Sequenom is in the process of validating its SEQureDx test in a company-run study that has enrolled 858 women from across the country. The latest analysis of this study was unveiled Wednesday night at a Sequenom-sponsored investor event being held in conjunction with the Society for Maternal-Fetal Medicine's annual meeting.

The company intends to launch a commercial version of the Down syndrome genetic screening test in June.

Ultimately, Sequenom believes that its genetic test will prove to be superior and safer than current screening methods and diagnostic tests like amniocentesis and replace them all. If that occurs, Sequenom could stake a large claim to a $2 billion-a-year prenatal testing market.

Down syndrome occurs when a baby has three copies of chromosome 21 instead of the normal two copies. Babies born with Down syndrome grow up with developmental and mental disabilities and abnormal facial appearances.

Today, pregnant women deemed to be at higher risk are screened for Down syndrome using a combination of ultrasound and blood tests. These screens typically detect between 85% to 90% of babies with Down syndrome and carry a false positive rate of around 5%.

To definitively diagnose Down syndrome, women undergo an invasive procedure like amniocentesis or chorionic villus sampling, which collects fetal cells and counts the number of chromosome 21s.

The Sequenom test relies on new technology that can detect minute amounts of fetal RNA in a mother's bloodstream. Using a small sample of blood taken from the mother, Sequenom isolates fetal RNA and determines whether there are two copies of chromosome 21 (a healthy baby) or an extra copy of the chromosome, which would indicate Down syndrome.