New Data Publication in the American Journal of Obstetrics & Gynecology Highlights Proprietary Algorithm for Aria’s Non-Invasive Prenatal Assay

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Results Demonstrate Enhanced Accuracy in Detecting Both T21 and T18 Abnormalities

San Jose, Calif., Jan. 27, 2012 – Aria Diagnostics, a molecular diagnostics company, today announced the publication of a study showing that Aria’s technology -- a directed non-invasive approach to cell-free DNA (cfDNA) analysis in maternal blood using a proprietary algorithm -- enabled non-invasive detection of Trisomy 21 (associated with Down syndrome) and Trisomy 18 (associated with Edwards syndrome). The data appear online in the American Journal of Obstetrics & Gynecology (AJOG) at

“The encouraging results from this study suggest that the novel algorithm is a good complement to the directed cfDNA assay, as it allows for the calculation of an individualized risk score for Trisomy 18 and 21,” explained Howard S. Cuckle, PhD, president of the International Society for Prenatal Diagnosis, professor at Columbia University Medical Center, New York. “The ability to selectively sequence the DNA, in combination with the algorithm, shows great promise for increasing efficiency and applicability with this technology.”

The study examines use of Aria’s highly multiplexed assay, known as Digital Analysis of Selected Regions (DANSRTM), which utilizes innovative biochemistry to efficiently analyze patient samples. It also introduces an algorithm known as Fetal-fraction Optimized Risk of Trisomy Evaluation (FORTETM) that incorporates the results of the DANSR assay, the percentage of fetal DNA in the patient’s sample and clinical information such as the maternal age to provide a risk score for each patient.

Titled, “Non-invasive Prenatal Detection and Selective Analysis of Cell-free DNA Obtained from Maternal Blood: Evaluation for Trisomy 21 and Trisomy 18,” the study involved 338 women 18 years and older who were of at least 10 weeks gestational age and pregnant with only one fetus. They were divided into a training set designed to optimize the assay and algorithm, and a blinded test set used for validation. The algorithm produced individualized trisomy risk scores for T21 and T18 for each subject, and accurately classified all T21 and T18 cases from all non-trisomic cases.

“These data support previous research to show that our approach should make routine non-invasive testing for common trisomies possible and affordable,” said John Stuelpnagel, DVM, executive chairman at Aria Diagnostics. “We are excited to see how the algorithm continues to perform with the Aria test in additional studies.”

An independent blinded study evaluating the accuracy of Aria’s test was also published online recently and is accessible at This additional study, authored by Professor Kypros Nicolaides, MD, of Harris Birthright Research Centre for Fetal Medicine at King’s College Hospital in the United Kingdom, was made possible by a grant from the Fetal Medicine Foundation.