Researchers at Columbia University Fertility Center, with funding from the National Institutes of Health, have developed a new test that can detect chromosomal abnormalities in an embryo or fetus much quicker than currently available technology, and at a fraction of the cost.
The test, known as STORK (Short-read Transpore Rapid Karyotyping), could impact treatment for patients who have miscarried, are pregnant or are undergoing IVF.
“STORK testing takes hours instead of days to weeks, costs a couple of hundred dollars instead of a couple of thousand dollars, and can be done at the point of care instead of shipping to a reference lab,” Dr. Zev Williams, lead author of the study, told HuffPost.
Like currently available tests, STORK identifies aneuploidies — or chromosomal additions or deletions — that are “by far, the most common cause of miscarriage and major cause of developmental delays and congenital anomalies,” said Williams. The test also indicates the sex of the embryo or fetus.
Examples of aneuploidies include trisomy 13, or Patau syndrome, which affects multiple organ systems and is usually fatal before a child turns 1, and trisomy 18, or Edwards syndrome, which often results in miscarriage or stillbirth. Trisomy 21, or Down syndrome, is the best-known of these conditions, but one of the least severe. While Trisomy 21 makes miscarriage and stillbirth much more likely, it’s also possible for people with Down syndrome to live well into adulthood.
Note that while STORK and other karyotyping tests detect aneuploidies, they do not detect monogenic diseases that result from a mutation of one gene. Testing for these diseases, such as sickle cell anemia and cystic fibrosis, would require an additional test.
The technology used by the STORK test analyzes DNA samples at 15,000 times the speed of current methods, delivering results in under two hours. Current tests, which involve sending samples to a laboratory, require days or weeks of waiting for results.
In their testing, researchers examined 218 samples from embryo biopsies, miscarriages and pregnancies. STORK’s results matched the results of standard testing in all pregnancy samples and in 98% of embryo samples. The two tests did not have matching results for 10 miscarriage samples, but researchers later determined that the STORK results were accurate.
The STORK test involves a compact device that fits in the palm of a hand and can process up to 10 samples at a time, further reducing costs. The study team estimates that it will cost $200 to run one sample, but only $50 if 10 samples are run at a time. Current standard tests can cost thousands of dollars, and insurance companies often won’t cover genetic testing for a miscarriage if it’s the patient’s first.
Williams and his colleagues are currently waiting for approval from the New York State Department of Health in order to begin offering the test to Columbia patients.
The test’s availability could impact the timing and cost of IVF cycles. Currently, patients who opt for genetic testing of their embryos — usually so they can select those most likely to result in a viable pregnancy — have to freeze their embryos after they are biopsied, and then wait a month to transfer one or more into the uterus. With STORK, however, “an embryo can be tested in the morning and transferred in the afternoon,” said Williams. Patients would save the cost of freezing the embryos, which can be $5,000 or more. (Studies do not show a significant difference in success rates between frozen and “fresh” embryo transfers.)
In terms of pregnancy care, patients who have amniocentesis after 15 weeks or chorionic villus sampling (CVS) at 10-13 weeks would receive test results much more quickly. But the ability to act on those results would depend on where they live.
“For those living in states with the most restrictive abortion laws, unfortunately, this test won’t change much,” Donna Gregory, a nurse practitioner and professor of nursing at Regis College, told HuffPost.
Abortions in those states are now unavailable to patients who have been pregnant long enough to get tests like amniocentesis or CVS, even if the test results come back rapidly. But in a state like Florida, which currently bans abortion after 15 weeks, the speed of STORK testing could prove significant.
The test also relieves the psychological burden of awaiting results.
“Women and families waiting for the results of these tests when they are done based on suspicion and concern for the fetus experience a large amount of emotional stress,” said Gregory. “Having the ability to test in-office can alleviate this.”
“If the pregnancy loss was found to be genetically abnormal, that provides a sense of closure, ameliorates feelings of self-blame and guilt, and provides reassurance for [a patient's] next pregnancy.”
- Dr. Zev Williams
STORK’s low cost could make genetic testing after miscarriage much more widely available. It also simplifies the process. Currently, labs have to grow cells from a miscarriage, a task that can take weeks and is not always successful — sometimes leaving patients without answers.
“The most common reason for pregnancy loss is a chromosomal defect. This defect accounts for about half of all miscarriages,” Dr. Hugh Taylor, chair of obstetrics, gynecology and reproductive sciences at Yale, told HuffPost.
“The test will allow a rapid and inexpensive way to determine if this is the cause or if we need to look for other reason for the loss,” said Taylor.
Not everyone who miscarries wants to know genetic information about the pregnancy, but many people do. Amy Klein, who writes of her struggle to maintain a pregnancy in her book “The Trying Game,” told HuffPost, “when my fourth miscarriage tested normal, I knew it was not a problem of my age but my body.”
Klein is hopeful that greater access to testing will help people who lose a pregnancy make decisions moving forward. “Women who suffer multiple miscarriages are severely undertreated,” she said.
“If the pregnancy loss was found to be genetically abnormal, that provides a sense of closure, ameliorates feelings of self-blame and guilt, and provides reassurance for her next pregnancy,” Williams added.
While the test can’t deliver any information that isn’t currently available, its speed alone makes it noteworthy.
“I think there is something very encouraging about using the most advanced technologies to address fertility and pregnancy loss — two of the most ancient of human afflictions,” said Williams.
“There is a trend towards rapid self-testing as we have seen during COVID,” said Taylor. “Many tests that were traditionally performed only in laboratories are now conducted at home or in a physician’s office.”
“This particular test is far more complex than most simple home tests,” Taylor continued. “The successful development of a rapid and inexpensive option demonstrates that even very complex genetic tests can be simplified through clever use of modern technology to improve patient care.”