New Data from Ambry Genetics Show Substantial Increase in Diagnostic Yield, Further Supporting the Routine Use of RNA Genetic Testing for Hereditary Cancer Panels

November 05, 2019

FOR IMMEDIATE RELEASE

Ambry Genetics
1 Enterprise
Aliso Viejo, CA 92656

Based on data from a prospective, nationwide, multi-center pilot, adding RNA genetic testing to DNA testing identified more disease-causing mutations compared to DNA-only testing.

Results from a separate study demonstrated that genetic testing results frequently lead to changes in patient care

(Aliso Viejo, CA) November 5, 2019: Ambry Genetics (Ambry), a leading clinical genetic testing company, will present at this week’s National Society of Genetic Counselors Annual Conference in Salt Lake City, Utah, data from the first 2,500 patients that received +RNAinsight™, paired RNA and DNA genetic testing for hereditary cancer risk. Data revealed that +RNAinsight resulted in a substantial increase in diagnostic yield, identifying more patients with genetic mutations (disease-causing errors in our DNA) compared to DNA testing alone. This is the first major increase in diagnostic yield for hereditary cancer risk in over 10 years, since the adoption of deletion/duplication testing. Through +RNAinsight, Ambry is the first and only lab to offer paired RNA and DNA genetic testing for hereditary cancer as a commercially available clinical test.

Standard DNA testing for hereditary cancer risk excludes large portions of DNA, thereby missing some mutations. In addition, DNA testing can produce inconclusive results and fail to determine that an error in our DNA increases cancer risk. These limitations impact patients and their families because doctors may not have the information needed to recommend appropriate preventive, early detection, or therapeutic steps. Additionally, relatives may not be referred for genetic testing and obtain the care they would otherwise have gotten if they had learned they had mutations.

Adding RNA to DNA testing overcomes these limitations for a substantial number of patients as it provides considerably more evidence than DNA testing alone about whether our DNA has mutations. Ambry will present data showing that paired testing with +RNAinsight both (1) identified new mutations that would have been missed with DNA testing alone, and (2) clarified inconclusive results as disease-causing. DNA testing alone would have found these latter results as inconclusive and left doctors without this crucial information.

“These findings further demonstrate that hereditary cancer panels should include both RNA and DNA genetic testing,” said Rachid Karam, MD, PhD, lead study author and Director of the Translational Genomics Lab at Ambry Genetics. “By looking at regions of the gene that other tests don’t, +RNAinsight reduces false negatives, maximizing the number of patients who learn they have higher risks for hereditary cancer.”

The data show an overall relative increase in diagnostic yield of 6.7 percent compared to DNA testing alone, increasing by as much as 19 percent for specific genes. For example, for BRCA1, 14 percent more patients learned they had a mutation that increased their cancer risks than would have if they had only received DNA testing. Moreover, by analyzing regions of DNA known as introns that standard DNA testing alone does not assess, paired RNA and DNA testing found completely new mutations that DNA-only testing would not have found or identified as disease-causing. Thus, patients who learn they have mutations from paired testing can get the appropriate medical treatment while those who undergo standard DNA testing alone might not because they may never learn they have those mutations.

RNA genetic testing also resulted in an overall 4.5 percent relative decrease in the number of patients that would have received inconclusive results with DNA testing alone, reducing inconclusive results by as much as 9 percent in specific genes. As with identifying entirely new mutations, clarifying results can let more patients with mutations learn they have them.

+RNAinsight is now available through doctors and genetic counselors around the country. For more information on RNA genetic testing, please go to www.ambrygen.com/RNAinsight.

In addition to this paired RNA and DNA testing data, Holly LaDuca, Senior Manager, Clinical Affairs Research at Ambry, will present data from a survey sent to clinicians assessing how genetic testing results inform patient care.

Since January 2018, Ambry Genetics has provided surveys to all clinicians ordering hereditary cancer testing through Ambry both before and after they receive their patients’ genetic test results. In the first few months of offering the survey, 131 providers completed pre-and post-test surveys for 469 patients who received genetic testing. When genetic testing found mutations, changes to preventive screening recommendations were made for 62.1 percent of patients and surgical recommendations were made for 37.9 percent of patients. In addition, 40.9 percent of clinicians recommended genetic counseling changes, such as the testing of family members and discussions of reproductive risks.

“Management guidelines have been developed for numerous cancer-predisposition genes. However, data is limited on how these guidelines and genetic testing results impact patient care in the real world,” said Ms. LaDuca. “Preliminary data from this ongoing survey demonstrate that positive genetic test results frequently lead to changes in medical management.”

For the full list of studies that will be presented at NSGC, please see below: