Prenatal testing for inherited genetic conditions typically requires invasive procedures that carry some risk to the pregnancy. Natera announced it will expand its Fetal Focus noninvasive test from five genes to 20 genes, with plans to launch the expanded panel in Q4 2025.
Key Points
- The expanded Fetal Focus test will screen for 20 inherited genetic conditions using cell-free DNA analysis from a maternal blood sample, up from the current five-gene panel launched in August.
- The test uses Natera’s LinkedSNP technology, which the company states is designed to detect homozygous cases where a fetus inherits the same disease-causing mutation from both parents. The company acknowledges that clinical performance should be rigorously established in prospective, well-designed clinical studies.
- Initial results from the EXPAND prospective trial indicated the test identified five out of five homozygous cases. The study enrolled approximately 1,700 patients from academic medical centers and maternal fetal medicine clinics, with all outcomes confirmed by diagnostic testing.
- Since the initial launch, Fetal Focus identified a pregnancy affected with cystic fibrosis that was homozygous for the delta F508 mutation, which had been missed by another laboratory, according to the announcement.
- The company notes that all outcomes in the EXPAND trial, including both positive and negative results, are being confirmed through prenatal or postnatal diagnostic testing.
The expanded panel aims to enable prenatal detection of severe, early-onset inherited conditions through a maternal blood draw.
The Data
- Following FDA warnings in 2022 about noninvasive prenatal tests for rare genetic conditions, reporting found that false positive results can reach 80% to 93% of the time. The agency has not authorized, cleared, or approved any NIPT, as they are marketed as laboratory-developed tests.
- The EXPAND trial, initiated in 2023, enrolled approximately 1,700 patients representing what the company describes as a diverse, multi-ethnic population.
- Initial readout from EXPAND showed the test successfully identified five out of five homozygous cases, according to the recent announcement.
- The expanded 20-gene panel is planned for launch in Q4 2025, building on the five-gene test that launched in August.
- The company operates ISO 13485-certified and CAP-accredited laboratories under CLIA in Austin, Texas, and San Carlos, California, with tests supported by more than 325 peer-reviewed publications, according to the announcement.
- Natera faces competition in single-gene NIPT from BillionToOne, which has captured approximately 15% of the US prenatal testing market with its UNITY test that screens for inherited disorders without requiring paternal DNA samples.
Industry Context
Homozygous cases are challenging to detect, and the initial readout from the EXPAND trial showed that Fetal Focus successfully identified 5 out of 5 such cases.
Ramesh Hariharan, general manager of women’s health at Natera
Detecting inherited genetic conditions prenatally has traditionally required invasive procedures such as amniocentesis or chorionic villus sampling, which carry small risks to the pregnancy. Noninvasive prenatal testing using cell-free DNA from maternal blood has been available for chromosomal conditions, but single-gene disorders have posed technical challenges, particularly for homozygous cases where the fetus inherits identical mutations from both parents.
Natera’s approach analyzes fetal cell-free DNA circulating in the mother’s blood to determine whether a fetus has inherited disease-causing mutations. The company positions the EXPAND trial as designed to provide robust estimates of test sensitivity by confirming all results—both positive and negative—with diagnostic testing.
The expansion from five to 20 genes represents an attempt to broaden the range of detectable inherited conditions through a single blood draw. However, the company’s own statement emphasizes that clinical performance must be established through rigorous prospective studies.
