How Widespread Prenatal Testing for Microdeletions Can Hurt Patients and Why the Genetic Testing Industry Needs More Accountability

by Katie Stoll

The New York Times published an important investigative piece this week, exploring concerns about expanded prenatal genetic screening. Specifically, the article focuses on the practice of prenatal screening for the possibility of a microdeletion condition in the fetus. The authors Sarah Kliff and Aatish Bhatia walk readers through some of the microdeletions that are often included as part of prenatal cell free DNA screening and discuss issues with the way these tests are marketed as providing accurate results and certainty when in fact most positive screen results end up being false positive.  The article states that in interviews,

14 patients who got false positives said the experience was agonizing. They recalled frantically researching conditions they’d never heard of, followed by sleepless nights and days hiding their bulging bellies from friends. Eight said they never received any information about the possibility of a false positive, and five recalled that their doctor treated the test results as definitive.”

The results of this investigation into patients’ experience with these screenings are so disheartening, and unfortunately are also consistent with what we have seen through our work at Genetic Support Foundation (GSF).

How Misleading Prenatal Screenings for Microdeletions Hurts Patients

The testing laboratories that market and sell prenatal screening tests often persuasively claim in their messaging that these tests are simple and accurate. The lab reports issued by the companies also often give a feeling of certainty stating that a chromosomal difference is “detected.”

It is hard for both patients and providers to accept that these are screening tests that show only a probability of a genetic/chromosomal condition, and that in many cases the likelihood of a false positive far outweighs the likelihood of a true positive result.

So what is driving this expansion of testing, if these conditions that these tests screen for are so rare and their predictions are so often incorrect?  The simplest explanation is the labs that sell these tests are largely motivated by profit. There is financial incentive to offer bigger tests, even though this may not always be in the best interest for patients.

How Profits – Not Best Practices – Are Driving the Cell Free DNA Screening Industry

Prenatal cell free DNA screening first came on the market for testing for Down syndrome in 2011 with a test offered by the company Sequenom. In 2013 Sequenom expanded their cfDNA test to include screening for select microdeletion syndromes. Many other companies also followed suit with similar tests. The addition of microdeletions to cfDNA was initially a business strategy for expanding the testing market to include all pregnant individuals because despite the rarity of the selected microdeletions, their incidence—unlike that of Down syndrome –is not linked to maternal age. And to increase fees as labs can bill more for adding the analysis for microdeletions to their test.

There are many concerns about microdeletion testing, however, including the fact that it is challenging to screen for microdeletions, and this taken with the rarity of these conditions, means that the predictive value of the testing is usually quite low. Generally, with screening tests, the rarer the condition, the more likely that a positive result will be a false positive. For these reasons the American College of Obstetricians and Gynecologists (ACOG) and the American College of Medical Genetics and Genomics (ACMG) recommend against including microdeletion screening on prenatal cfDNA screening. 

Although ACOG, ACMG, and other organizations that produce guidelines about the best practices for care for patients recommend against inclusion of microdeletions, labs continue to offer ever-expanding panels in an effort to grow their market share. These companies put tens of millions of dollars into marketing and face no accountability when the marketing is misleading or untrue. Testing companies have even joined forces to create non-transparent industry lobbying groups to gain better reimbursement for their testing, including from state Medicaid programs.

Why More Accountability for the cfDNA Industry Is Essential

In practice, this plays out with obstetrical care providers (obstetricians, midwives, family medicine doctors, etc.) overwhelmed with the growing number of genetic tests and changing guidelines. Add to this that they have brief appointments in which they need to cover many topics and concerns related to pregnancy. Providers also face a real concern about the liability that could come from a wrongful birth lawsuit if a condition is not identified when there is a test available. The salespeople make it easy to order their test dealing with the billing issues, leaving brochures that often contain misleading information, and promising that their company genetic counselors will provide follow-up for their patients at no extra charge. Given all these factors, it is much more likely that the provider may just present these tests as routine, rather than have the kind of nuanced conversation with patients that would support an informed choice of whether or not to undergo these screenings. 

At the Genetic Support Foundation, we believe that people deserve to have up-to-date, accurate and unbiased information about these tests before deciding if they should undergo them and fully understand what they screen for, what a positive result means, and what the possibility of a false positive result or uncertain information means for them. 

If you are considering this testing and feel you have not been given enough information to make the best choice for you, or if you have already had this testing and are wondering about your results and what they mean, please don’t hesitate to reach out. Our team of independent genetic counselors are here to help.

At GSF, we’re also working to advocate for accurate, unbiased access to genetic counseling for all to help reduce the problems brought about by profit-driven testing companies providing genetic counseling services to those who take their tests. With all that profit from this growing industry comes an increasing need to regulate the market and protect patients from predatory companies, misleading marketing, poor information, and bad testing and information practices. You can help. Learn more at