Most parents have probably heard about the major genetic disorders that can be tested for prior to birth such as trisomy 21 (Down Syndrome). Relatively few people, however, may know about other more “subtle” genetic abnormalities that can be discovered prenatally. Medgadget recently had the opportunity to interview Natera‘s CTO, Jonathan Sheena, about his company which specializes in non-invasive prenatal testing (NIPT). Through the Q&A we learned more about NIPT as well as the coming shortage of genetic counselors that may limit access to and engagement with one’s genetic information.
Shiv Gaglani, Medgadget: What is Natera’s mission and who is your market?
Jonathan Sheena: Natera’s mission is to safely give expecting parents the most comprehensive understanding of the fetal genome to date. We focused our backgrounds in statistics, molecular biology and engineering to develop Panorama, a highly accurate, bioinformatics-based non-invasive prenatal test (NIPT), which uses a blood draw from the mother to detect specific genetic abnormalities, including trisomy 21 (Down syndrome), 13 (Patau syndrome), 18 (Edwards syndrome) as well as certain sex chromosome abnormalities such as monosomy X.
Medgadget: Can you discuss the novel technologies that Natera uses? What innovations have made it possible?
Sheena: We set a goal for ourselves to build the most accurate non-invasive prenatal aneuploidy diagnostic on the market. To achieve that goal we created the NATUS platform which uses a highly multiplexed SNP assay and combines genetic information from the mother (and father if available) with data from the Human Genome Project. NATUS cleans up noisy fetal measurements and statistically determines whether chromosomal abnormalities are present or not in the fetal DNA.
This approach overcomes the limitation of first generation NIPT technologies currently on the market, which use quantitative approaches that count the number of sequence reads on a test chromosome and compare those to a reference chromosome; excesses above a threshold are called trisomies. While this approach works well enough for trisomy 21, published data show that accuracy declines when testing other syndromes. The SNP-based NATUS platform overcomes the limitations of quantitative problems and has shown it is consistently accurate across all chromosomes.
In addition, Natera’s technology enables the detection of triploidies, uniparental disomies and much more accurate sex chromosome abnormality detection. Natera recently presented data at the annual meeting of the Society for Maternal-Fetal Medicine, which demonstrated Panorama’s sensitivity of greater than 99 percent when detecting chromosomal abnormalities trisomy 21, 18 and 13, and 92 percent when detecting monosomy X in over 700 maternal blood samples. In addition, Panorama demonstrated a specificity of 100 percent with no false positives for all the syndromes tested.
Medgadget: What opportunities and challenges exist in terms of getting Natera’s products adopted by the various stakeholders (e.g. providers, hospitals, patients, insurers, etc.) ?
Sheena: Our immediate goal is to provide patients and physicians access to Panorama. We have partnered with major distributors, including Quest, Bio-Reference and ARUP to make Panorama available to the broadest patient population possible. In addition, we are also offering a generous patient assistance program to help should income level be a hindrance.
Broad access also requires insurance company support. A significant milestone for the NIPT space was the announcement by multiple major insurance companies of medical policies in support of NIPT, including Aetna, United Healthcare and Wellpoint. Another success for the space overall was the announcement of the American Congress of Obstetricians and Gynecologists’ (ACOG) recommendation of the use of NIPTs for women with high-risk pregnancies, which will likely lead to additional payers supporting coverage of the tests as well.
Looking ahead, access to genetic counseling will be a challenge — even in the United States. NIPTs should only be offered when patients have received pre-test counseling. However, there are just over 3,000 certified genetic counselors in the United States today, and only about a third of them counsel on prenatal testing. As prenatal genetic testing broadens, we will see a bottleneck of qualified genetic counselors. Natera has a staff of in-house genetic counselors who are helping educate and emphasize the importance of receiving counseling, but the field clearly is heading for a shortage.
Medgadget: What are you most excited about in terms of Natera’s future? And in terms of prenatal testing or medical technology in general?
Sheena: We are excited to see the expanding understanding of genotypic disease associations. Genetics now can explain far more abnormalities at birth than even ten years ago. For example, recent studies show that most prevalent ten microdeletions account for more clinically significant issues at birth than even trisomy 21. These advances are being driven partly by the plunging cost of genotyping tied with availability of large scale computing.
At Natera, we are anxious to build on the success of our Panorama launch by bringing these advancements to patients. Microdeletion detection, triploid detection and detection of inherited single gene disorders are a few of the projects we are exploring. Opportunities abound to shine light into the dark corners of disease.