For Immediate Release: Thursday, October 22, 2026, 11:00 a.m. U.S. Eastern Time
Media Contact: Evelyn Mantegani, +1 240-833-2014, [email protected]
Presented By: Michael Duyzend, MD, PhD, Massachusetts General Hospital, Broad Institute, Boston Children’s Hospital, Harvard Medical School
Current cell-free DNA screening in pregnancy primarily detects common chromosome abnormalities and selected genetic conditions. Identifying a broader range of fetal genetic variants generally requires an invasive procedure such as amniocentesis. Researchers have now developed a comprehensive noninvasive fetal sequencing (NIFS) blood test that surveyed almost all fetal genes and detected 97.2% of genetic diagnoses identified through invasive whole genome sequencing.
The researchers applied the NIFS test to 547 pregnancies, including those with and without fetal structural anomalies. NIFS analyzes nearly 23,000 genes using cell-free DNA circulating in the pregnant patient’s blood. Among 72 cases with a molecular diagnosis established through invasive testing, NIFS detected 70, including all 10 diagnostic copy-number variants, all autosomal dominant and X-linked conditions in the study, and all but two recessive conditions. The test did not report one recessive condition that included a small deletion on the paternal chromosome that was below the current NIFS detection threshold, and NIFS detected, though incorrectly genotyped, one homozygous fetal sequence variant.
Researchers also compared more than 5 million fetal variant genotypes from NIFS with matched invasive genome-sequencing results. For variants that arose spontaneously or were inherited from the biological father, NIFS achieved a median sensitivity of 97.3% and precision of 99.1%. NIFS also addressed the technical challenge of maternally inherited variants, producing high confidence genotypes at more than 80% of evaluated sites, with sensitivity and precision above 96% in that subset.
NIFS additionally discovered and characterized unusual cell-free DNA patterns associated with circumstances including a vanishing twin, maternal bone marrow transplantation, sex-chromosome mosaicism, and a molar pregnancy in an unrecognized twin gestation.
The findings suggest that broad fetal sequencing from a maternal blood sample could eventually reduce reliance on invasive diagnostic procedures and provide a platform for screening. However, larger clinical trials, further validation, and reporting standards tailored to different prenatal contexts are needed before routine implementation.
About the American Society of Human Genetics (ASHG)
The American Society of Human Genetics (ASHG) is the leading global organization advancing the science of human genetics and genomics. Representing nearly 8,000 researchers, clinicians, genetic counselors, educators, and other professionals, ASHG drives progress in understanding the human genome and its role in health and disease. The Society fosters innovation and collaboration through its flagship events and publications—including the ASHG Annual Meeting and its peer-reviewed journals The American Journal of Human Genetics and Human Genetics and Genomics Advances. ASHG also champions science advocacy, supports the next generation of genetics professionals, and promotes responsible policies and public engagement in genetics. Learn more at www.ashg.org.
6120 Executive Blvd, Suite 500 | Rockville, MD 20852 | 301.634.7300 | [email protected] | www.ashg.org
Connect with ASHG on Bluesky (@geneticssociety.bsky.social) |
X (@GeneticsSociety) | Facebook | LinkedIn