BillionToOne, a venture-backed precision diagnostics company, is presenting series of posters at 2020 ACMG Annual Clinical Genetics Meeting on its single-gene NIPT technology and clinical data.
UNITYTM improves clinical specificity for cystic fibrosis carrier screening
UNITYTM is the only prenatal screen that tests cell-free fetal DNA for cystic fibrosis, spinal muscular atrophy (SMA), sickle cell disease, and alpha and beta thalassemia using just one tube of blood from the mother. Since its commercial launch in June 2019, UNITY has pioneered a new carrier screening paradigm where pregnant mothers can directly learn fetal risk for common and severe single-gene disorders from a simple blood draw from the arm, as opposed to only learning her carrier status, which by itself, is not actionable without the paternal carrier status information.
At one poster titled “Single-gene NIPT for Cystic fibrosis Improves Clinical Specificity of Carrier Screening“, the clinical team talks about how the ability to reflex to single-gene NIPT has expanded the specificity of cystic fibrosis carrier screening. Traditionally, maternal carrier screening for CF only returns positive results when an individual carries a likely pathogenic or pathogenic variant for CF. Mothers who carry a VUS or a less severe classification of pathogenicity are not informed, and thus paternal screening is not prompted. Carrier screening using reflex CFTR NIPT bypasses paternal prompting by examining the inheritance of paternal alleles in the instant conception. BillionToOne has developed a paternal CFTR NIPT screen that examines fetal DNA. Thus at-risk pregnant women that are carriers of these less severe variants can be ruled out as pregnant with affected CFTR fetuses when paternal alleles are not seen in the screen. On the other hand, when CFTR NIPT identifies that the fetus inherited pathogenic alleles from the father, the clinical team can then combine that information with the maternal variant and make more informative clinical assessment on the fetal risk. It has allowed UNITYTM to make calls on milder CFTR variants when it is co-present with pathogenic variant inherited from the father.
NIPT examines the paternal allele automatically thus allowing a patient to learn her carrier status and fetal risk simultaneously. This dual notification process provides immediate reassurance about the current pregnancy while also informing the patient about her future reproductive risk. The vast majority of conceptuses of mothers carrying likely pathogenic or pathogenic alleles will be unaffected with disease. Thus the clinical specificity of the test is improved through this strategy, and studies are underway to quantify the noted improvement.
UNITYTM publishes more clinical data on single-gene NIPT for cystic fibrosis, SMA, and sickle cell disease/beta-thalassemia
At four other poster presentations, BillionToOne research team will present more clinical data on single-gene NIPT for cystic fibrosis (CFTR gene), SMA (SMN1 gene), and sickle cell disease/beta-thalassemia (HBB gene).
One of the posters titled “A novel, non-invasive prenatal screening methodology identifies a healthy fetus from a mother with a complex sickle cell disease genotype” has been selected as top-rated posters.
American College of Medical Genetics (ACMG) is the only nationally recognized interdisciplinary professional membership organization that represents the interests of the entire medical genetics team including clinical geneticists, clinical laboratory geneticists, and genetic counselors. Its annual meeting will be held at Henry B. González Convention Center in San Antonio on March 17 – 21. Poster session will be held during March 18-20.
BillionToOne will also exhibit its UNITYTM offering at the ACMG conference. For any clinical ordering, research collaboration, or media inquiries, please email [email protected]
Update on March 8, 2020: ACMG Annual Meeting was cancelled due to continuing spread of covid-19.