Analysis of rare circulating fetal cells make possible a new type of noninvasive genetic prenatal testing

HOUSTON, Oct. 24, 2016 /PRNewswire/ -- Researchers at Baylor College of Medicine and RareCyte, Inc., have determined that it is feasible to develop a prenatal, noninvasive genetic test based on rare fetal cells that are present in the mother's blood. The study appears in the October issue of the journal Prenatal Diagnosis.

"Fetal cells were first reported in the circulation of pregnant women more than 40 years ago, and people have been hoping since that time to be able to use them for prenatal diagnosis," said senior author Dr. Arthur Beaudet, who is Chair of Molecular and Human Genetics at Baylor. "With the emergence of RareCyte's platform technology for the identification of rare circulating cells and the retrieval of single cells, this is now possible."

"We are pleased to be working with Dr. Beaudet and his team at Baylor on this critical project. This is a milestone achievement in prenatal research and for RareCyte," said Ron Seubert, chairman and CEO of RareCyte.

"Our goal in this project was to determine whether it was possible to collect trophoblasts present in the mother's circulation in numbers sufficient for further genetic analysis," said Beaudet. Trophoblasts are cells from the placenta and carry the fetus's entire genetic material.  The main obstacle to achieving this goal is that there are very few fetal cells in the mother's blood, and they are very fragile.

RareCyte has developed a platform that identifies individual fetal cells using an automated image scanner that mechanically retrieves them with an extremely precise needle having a tip opening less than half the width of a human hair.  About two tablespoons of maternal blood has hundreds of billions of red blood cells and hundreds of millions of white blood cells but only 20 to 40 fetal cells.  The research group commonly recovered 3 to 10 or more fetal cells for analysis by various molecular methods, including next generation DNA sequencing.

Although other noninvasive methods for genetic testing are currently widely available, they have limitations. For instance, cell-free DNA testing cannot reliably detect very small changes in the fetal genome.  The authors reported identification of a gene deletion between 2 and 3 million base pairs long, which was described as "well below the limits of resolution" for currently available plasma-based non-invasive pre-natal testing.  

If the test can become routine practice in current and future forms, Beaudet anticipates that it could be transformative for prenatal diagnosis, offering comparable information to that which can be obtained by amniocentesis and chorionic villus sampling. He estimates that a test might be available to the public in one to two years.

Researchers at Drexel University College of Medicine and Texas Children's Hospital also participated in the study. 

About RareCyte, Inc.

RareCyte is a life science company that offers high-performance easy to use, next-generation tools for the analysis and capture of rare, individual cells from liquid biopsies and tissue samples. RareCyte's systems are used by academic institutions and commercial organizations for a range of applications in oncology, prenatal testing and infectious disease. For more information about RareCyte, visit www.rarecyte.com. 

About Baylor College of Medicine

Baylor College of Medicine (www.bcm.edu) in Houston is recognized as a premier academic health sciences center and is known for excellence in education, research and patient care. It is the only private medical school in the greater southwest and is ranked 20th among medical schools for research and 9th for primary care by U.S. News & World Report. Baylor is listed 20th among all U.S. medical schools for National Institutes of Health funding and number one in Texas. Located in the Texas Medical Center, Baylor has affiliations with seven teaching hospitals and jointly owns and operates Baylor St. Luke's Medical Center, part of CHI St. Luke's Health. Currently, Baylor trains more than 3,000 medical, graduate, nurse anesthesia, physician assistant and orthotics students, as well as residents and post-doctoral fellows. Follow Baylor College of Medicine on Facebook (http://www.facebook.com/BaylorCollegeOfMedicine) and Twitter (http://twitter.com/BCMHouston).

SOURCE RareCyte, Inc.

Related Links

http://www.rarecyte.com