The Changing Landscape of Genetic Counseling

The landscape of the genetic counselor workforce has shifted dramatically in recent years, in large part due to new opportunities for genetic counselors in genetic testing laboratory settings.  According to the Professional Status Survey conducted by the National Society of Genetic Counselors, the number of genetic counselors who report a laboratory as their primary work setting has doubled in the past 4 years and nearly tripled in the past 10, with 21% of genetic counselors reporting a laboratory setting as their primary workplace in 2016.  And this likely under-represents the percentage of genetic counselor who are employed by laboratories, as many who work for labs but see patients in clinics likely report their primary work setting as clinical.  

 

In an analysis of genetic counselors licensed in the state of Washington (presented at the NSGC meeting in 2016) we noted that 42% of genetic counselors were employed by commercial laboratories in 2015 as compared 22% in 2011.  At the same time, the percentage of genetic counselors licensed in Washington state in clinical positions decreased  from 60% in 2011 to 42% in 2015.  

 

While genetic counselors play important roles in laboratory settings, what does this shift in employment mean for the field of genetic counseling?  What does it mean for patient care at a time when genetic counseling services are more needed than ever?  

 

Many hospitals are struggling to recruit and retain genetic counselors for their practices and are looking for alternatives when there aren’t independent genetic counseling services locally available.  One option many medical practices are relying on is genetic counseling services provided by the testing laboratories.  

 

While lab-based genetic counseling services are filling an important need, there is a conflict of interest inherent in this arrangement.   Genetic counselors’ primary objective has historically been to help patients navigate difficult medical genetic information and decisions, supporting their autonomy.  But as laboratory employees, genetic counselors must also consider their employer’s interests, which includes increasing the uptake of genetic testing.

 

Challenges regarding conflict of interest in research and healthcare are not new, however this is an area of increasing concern in genetics.   

 

For more on this topic check out our commentary recently published in Genetics and Medicine and read our recent post, published on Harvard Law Bill of Health blog, written with our colleagues Marsha Michie and Megan Allyse.

 

An important part of our mission at Genetic Support Foundation is to address issues related to conflict of interest and to provide options for independently developed educational resources for patients and providers and genetic counseling services that are free from the commercial bias.  


Chromosomal Microarray (CMA)

Chromosomal microarray (CMA) is a technology that the American College of Obstetricians and Gynecologists now recommends be offered as a first-tier test for any woman undergoing diagnostic testing to replace the standard karyotype that has been used in practice for prenatal diagnosis for decades. This is a big change in practice; while the result may be an increase in the number of genetic differences that can be diagnosed through prenatal testing, it also comes with more uncertainty for expectant parents and healthcare providers who are trying to make sense of the results that may come from this testing.

 

First let me give some background on why the CMA test is different than the karyotype using the analogy of a library.  The nucleus of each of our cells contains our genetic information.  Imagine the nucleus to be like the library of the cell.  Each of us have about 20,000 pairs of genes, and each of these genes could be considered to be like an individual instruction book that tells the body how to build a specific protein that will have a specific job in our body.  The proteins that are built from our genes do everything that our bodies need to grown and function.  Our genes, (aka instruction books) are organized on chromosomes.  In this analogy, consider each chromosome to be like a large bookcase.  

 

The karyotype is a picture of the chromosomes and basically allows us to look at and count these bookcases.  In doing this we can see if there are any extra or missing bookcases (chromosomes).  Typically humans have 23 chromosomes inherited from their mother and 23 from their father in matched pairs, so 46 all together.  An extra or missing chromosome causes specific genetic conditions.  For instance, a baby with Down syndrome has inherited an extra copy of the 21st chromosome.    

 

The karyotype can also allow us to see if there are big structural changes in the chromosomes.  You could imagine this to be a scenario in which a few book shelves had been completely removed from the bookcase (so now a 10 shelf bookcase is a 7 shelf bookcase, for example).  This type of big change can be seen in looking at a picture of the chromosomes.  

 

The chromosomal microarray (CMA) test is different in that it allows us to see smaller genetic changes than can be seen by looking at the karyotype.  These changes are often referred to as Copy Number Variants, or CNVs.  A CNV is a segment of genomic information that has been duplicated or deleted.  So think of this as the equivalent of a few books on a shelf that have been removed (a deletion) or there are multiple copies of the same few books on the shelf (a duplication).  

 

Sometimes CNVs are known to cause genetic conditions resulting in health and developmental concerns.  Sometimes we are unsure what will result with certain CNVs.  Other times we see CNVs that appear to be completely normal variations, in which case we do not think they will cause any health or developmental concerns.  

 

With the karyotype, we usually have a pretty good idea of generally what to expect when we find  an extra or missing chromosome, or when there is a large change in the structure of a chromosome.  

 

But with CNVs, the meaning of the results is often much less clear.  Sometimes a CNV will be reported as being of “uncertain significance” which means that we just don’t know enough about it yet to determine if it is likely to cause health and/or developmental concerns or not.  Sometimes we find a CNV that we think will cause a health problem, but exactly what that will be or how severe it will be is unknown.  Sometimes when there is uncertainty, it will be recommended to test the parents to see if ether of them also have the same CNV.  This may provide some reassurance if a parent has the same CNV and they are in good health.  But we know there can be differences in how these variants are expressed from parent to child.  Furthermore, there can be situations in which a parent learns they also have the variant identified in the baby or their child, and rather than providing reassurance it leads to more questions.  Is there something wrong with me?  Did I pass on something harmful to my baby?  

 

Formerly, the American College of Obstetricians and Gynecologists recommended chromosomal microarray be considered  as a prenatal testing option in instances where there were abnormalities seen on ultrasound.  This is because in about 6% of those cases, CMA would provide an explanation that karyotype could not.  In other words, there would be a CNV (a few extra or missing books on a shelf) that karyotype could not see that could provide an explanation for the ultrasound findings.  

 

Research has found that in cases where ultrasound and karyotype are normal, a significant CNV that is believed to be likely associated with some health or developmental effect will be seen in 1.7% of cases.  Considering this, ACOG now recommends that CMA be made available to ALL women considering diagnostic testing such as amniocentesis.  

 

This means that more babies will be diagnosed with genetic conditions that would not have been identified from the traditional karyotype test.  It also means that many more families will be receiving information about their babies that may be unclear.  As genetic tests become increasingly complex, it is of utmost importance that women and couples receive pretest genetic counseling so that they can really understand all of the potential benefits, drawbacks, and uncertainties inherent with these tests.  


New Practice Guidelines for Prenatal Genetic Testing

Important guidelines in the area of prenatal genetics were recently published in the journal, Obstetrics and Gynecology (aka “The Green Journal”).  The American College of Obstetricians and Gynecologists (ACOG) and the Society of Maternal-Fetal Medicine (SMFM) collaborated on two new important references:  Practice Bulletin #162 Prenatal Diagnostic Testing for Genetic Disorders, and Practice Bulletin #163 Screening for Fetal Aneuploidy.  These are the first updated guidelines on these topics in nearly a decade and each offers a thorough assessment on currently available prenatal testing technologies as well important points to consider for any provider who provides prenatal care.  They are companion pieces and we encourage you to read them in their entirety when you have an opportunity. Below we summarize the highlights.  
Practice Bulletin number 162:  Prenatal Diagnostic Testing for Genetic Disorders

In 2007 ACOG shook things up by stating that all women (not just those deemed to have a higher chance to have a baby with a genetic condition) should have the option to undergo prenatal diagnostic genetic testing.  This recommendation did not change with the updated guidelines.  ACOG/SMFM still contend that all women should have the option of prenatal testing, including diagnostic tests such as amniocentesis and chorionic villus sampling (CVS). What has changed are the number of prenatal testing options.  With a growing number of testing choices, the decisions faced by expectant patients and couples are more complex than ever before. From the guideline:  

 

It is important that patients understand the benefits and limitations of all prenatal screening and diagnostic testing, including the conditions for which tests are available and the conditions that will not be detected by testing.”  

 

This is a great expectation!  Certainly even providers who think about these tests day in and day out struggle in deciphering the different benefits and limitations of each of these tests, as well as the variable conditions that each test may detect!  While it is perhaps a lofty goal, Genetic Support Foundation agrees wholeheartedly with the importance of this statement above. It is essential that individuals be provided enough information and context to make informed decisions when it comes to prenatal genetic testing.

Key updates with guideline #162:

  • Chromosomal microarray analysis should be the primary offered diagnostic method when ultrasound indicates structural abnormalities in the fetus.  Microarray should be made available to any patient choosing to undergo invasive diagnostic testing.  
  • New research indicates that the risk for miscarriage associated with amniocentesis and chorionic villus sampling may be lower than previously reported.  In the hands of experienced providers, the guideline suggests a miscarriage risk of 0.1% – 0.3%.  

Practice Bulletin number 163:  Screening for Fetal Aneuploidy

This document provides an excellent overview and nice comparison table of the various prenatal screening tests available for the assessment of chromosome conditions in the fetus. Technologies reviewed in detail include serum screening such as the triple and quad screening, combined screening such as first trimester screening, integrated screening and sequential screening and the more recently available cell-free DNA screening. The most important take away is that choices about prenatal screening options are complex.  

 

No one screening test is superior to other screening tests in all test characteristics. Each test has relative advantages and disadvantages. Screening for aneuploidy should be an informed patient choice, with an underlying foundation of shared decision making that fits the patient’s clinical circumstances, values, interests, and goals.”  

 

Key points with guideline #163:

  • Women who have any negative screening test should not be offered subsequent screening tests. Parallel testing with multiple screening tests should not be done.
  • Cell-free DNA screening is not a replacement for diagnostic testing.  
  • Any woman with a positive screening test including traditional serum screening or cell-free DNA screening results should be offered follow-up genetic counseling and the option to undergo diagnostic testing.
  • Women who undergo preimplantation genetic diagnosis should be offered aneuploidy screening and diagnostic testing.
  • Cell-free DNA screening for microdeletions is not recommended.  
  • Cell-free DNA screening is not recommended for multiple pregnancies.  

In the future, we will explore some points raised in these two guidelines in more detail including, the potential for toxic knowledge with chromosomal microarray testing and why genetic counseling in these situations. We will also explore the potential issues with predicting a lower risk of miscarriage associated with diagnostic testing at a time when some studies suggest that the risk may actually increase as fewer women undergo these tests and providers become less practiced in performing the procedures.  

One point that we strongly agree with is this:  

“Screening for aneuploidy should be an informed patient choice, with an underlying foundation of shared decision making that fits the patient’s clinical circumstances, values, interests, and goals.”  

Whether you are are patient, a healthcare professional, or policy maker, we at the Genetic Support Foundation hope that you will find information here on our website that will help support this goal.


Genetic Testing Catastrophe

Genetics and healthcare is a popular topic for television drama.  The ethical conundrums that arise with genetic testing coupled with the rarity of genetic conditions make for interesting stories.  As a genetic counselor, I often notice holes in the plot or inaccuracies in the way in which a genetic condition is portrayed or how a genetic test is discussed.  As much as I wish I could say that they got it wrong with the genetic testing story line in the sitcom, Catastrophe, writers and co-stars Rob Delaney and Sharon Horgan tell a story that seems so painfully true to life that I believe it must be based on lived experience.

Catastrophe tells the story of two 40-something singles who decide to make a go of family life together after a brief affair that results in an unplanned pregnancy.  The second season of Catastrophe will be available on Amazon on April 8th.  For those of you that have not yet watched the first season, it is a great time to get caught up.  Spoiler alert for those who would like to watch the show first – read no further.  Also a warning for those who are sensitive, this show earns its “Mature Audience” rating and they dive right into the adult content.    

The fourth episode of the show (season 1) tells Sharon’s prenatal genetic testing story.  She is first made aware that she had prenatal genetic screening at the time the doctor delivers the test results:  a 1 in 50 chance that the baby she is carrying has Down syndrome.  When Sharon replies that 1 in 50 doesn’t seem “that bad”, the doctor is quick to counter that this is “high risk” and he recommends an amniocentesis.  She refuses and rushes out of the office, beginning an emotional roller coaster ride.  

Just as Sharon seems to be settling from the initial surprise of the test results and their presentation, she gets a call from the obstetrician’s office.  In fact her test results were incorrect; the risk is actually 1 in 25.  With this, she is overcome by anxiety and decides to move forward with the amniocentesis, a diagnostic test that can tell her with certainty if the baby does or does not have Down syndrome. The amniocentesis results return showing that the baby does not have Down syndrome, news that she learns on a cell phone call while in the grocery store.  This news causes Sharon to lay down right in the middle of the grocery store aisle, perhaps to show the release of stress that came with the uncertainty of the wait for results.  The viewer is left to imagine much of what must have been going through Sharon’s mind with all of this testing.  What would she have done if the results showed that the baby did have Down syndrome?  While her emotional turmoil is obvious, Catastrophe leaves the answer to this question a mystery.   

I am grateful to Sharon and Rob for bringing this topic into the light with depth, wisdom, and wit.  I know so many have been through situations such as this but usually experience it all very privately.  Rob and Sharon revealed so many misunderstandings that may come up regarding the tests themselves and also expressed the real concerns and questions that expectant parents often have about what it would mean to have a child with a disability who would need more support and resources.  While they tackled these questions, I appreciated the way in which they approached discussions about disability, challenging stereotypes and preconceived notions.  So often when Down syndrome is discussed  in a prenatal context, information is presented in a negative and clinical manner.  With honesty and humor, Rob ponders whether some of Sharon’s negative assumptions are misinformed and recounts some of his past experiences that bring normalcy and humanity to the conversation.   

Sharon’s genetic testing experience is far too common, but also not at all the way it should be.  It is distressing that with decades of prenatal testing for Down syndrome, healthcare systems don’t do a better job of supporting women and couples.  High quality and up-to-date information about the tests and the conditions that they screen for is essential.  Equally important is creating the opportunity to help people find their way to put this information into the context of their own lives.  As prenatal genetic testing options expand to include an increasing number of conditions, and the commercial market forces that seek to increase use of these tests grow, supporting patients through these tests will be increasingly complex and also more important than ever.

In an ideal world, we would have seen Sharon and Rob given the opportunity to receive objective information about their prenatal testing options:  what the tests are, what they test for, what they can tell you and the possible next steps depending on the results.  The couple would have been encouraged to explore their values about these tests and their implications with each other before having any screening tests.  They would have been able to discuss their preferences with their doctor without judgment or coercion to choose a specific path.

If they elected to undergo prenatal screening, hopefully they would have had an opportunity prior to that decision to learn more about Down syndrome and the other conditions being screened for before getting those test results back.  And when the doctor delivered those screening results, ideally he would have done so in an objective manner leaving his subjective interpretation of the level of risk out of the conversation.  It would have gone something like this, “Sharon, I have the results from your genetic screening back.  They show that the chance that the baby has Down syndrome is 1 in 50 which is the same as 2%.  That means there is a 49 in 50 chance or 98% chance that the baby does not have Down syndrome.  If you would like to know for sure, you can consider undergoing a diagnostic testing known as amniocentesis which can tell you yes or no with certainty.  However, amniocentesis does have a small risk of miscarriage….”  And hopefully, prior to undergoing amniocentesis she would meet with a genetic counselor who could talk through all of this in more detail, to provide emotional  support to Rob and Sharon, to answer questions, explore misconceptions, hopes and fears, and to provide resources.

While in Catastrophe, fiction mirrors reality, it is important to know that individuals should always be given a choice as to whether or not this testing is done during pregnancy.  This is not just my opinion or that of the Genetic Support Foundation – it is supported by policy and practice guidelines throughout the United States, Canada, and Europe, including the UK where Sharon and Rob experienced prenatal care. Let’s continue to work towards improving the lived experience of women who are faced with decisions regarding prenatal testing.  Shows such as Catsorophe certainly help in that goal by shining a light to bring some awareness to these issues.  Healthcare professionals, must continue to strive to support informed decisions about these screens by providing objective information and resources.  


Introducing Carla from the Genetic Support Foundation Team!

First off, let me introduce myself. My name is Carla, and I am an integral part of the Genetic Support Foundation (GSF) Team. Well, at least the idea of “me” has become near and dear to the folks at GSF. I am actually the star of their new video on noninvasive prenatal testing (NIPT). But, I am really much more than that; I represent women who are pregnant and trying to sort through all of the prenatal testing options out there. How is one supposed to make these decisions? Pregnancy is hard enough with all of these hormones and food cravings. I have been driving through the Taco Bell drive-through every. Single. Day. They know me by name and my order by heart; I digress.

So, since I am going to be 35 at delivery, one of the tests my doctor offered me is noninvasive prenatal testing (NIPT). You may have heard this test called by other names such as NIPS, cell free DNA testing or brand names such as, Panorama, MaterniT21, Harmony, Verifi, informaSeq, etc. I guess this is a newer prenatal screening test, as I didn’t know about it during my last pregnancy in 2010 (apparently it came out in 2011). Last time around I decided not to have any screening because I was 30 and I wasn’t really worried. But this time things feel different, and everyone keeps talking about my age! What’s up with 35?

Anyway, here I am trying to weigh all of my options…should I have NIPT or should I consider going straight for more definitive answers and have a test like CVS or amniocentesis? Or, am I ok skipping all of them and just waiting until the baby is born to know if he/she has a genetic condition?

My partner and I just met with a genetic counselor, which was super helpful. The genetic counselor was able to help us by not only explaining all of our testing options, but providing us with some questions to think about to help us decide what testing, if any, was right for us given our beliefs, values, personality and needs. Genetic counselors don’t tell you what to do, they simply give you the information necessary to help you make a decision that is right for you!

Another thing that was helpful to me was being a part of the NIPT informational video produced by GSF that I mentioned earlier. You should really check it out! This video explains how NIPT works, what conditions it can screen for, what results can and cannot tell you and how to decide if this test is right for you.

I’m still in the process of figuring out my prenatal testing plans, but I know I am on the right track and the information at www.geneticsupportfoundation.org is equipping me to make a decision that is right for me!

On behalf of the GSF Team, thanks for reading Our 2 Strands!

Let’s stay in touch,

Carla

P.S. Send a comment to GSF through our Get Connected page if you can guess why my name is Carla! First person to guess correctly (who isn’t related to someone on staff) will win an official Genetic Support Foundation T-shirt!