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PLEASE PASS THE TISSUES

tissues

Yesterday I made the whole team cry. Thankfully it wasn’t because I was making unreasonable requests related to productivity or deadlines. Instead, I had slotted off the morning so that we could all watch a movie together—Decoding Annie Parker (2013; we borrowed it from a local library). Without spoiling the entire plot for our readers, suffice it to say that the movie, based on actual events, follows a woman (Annie Parker) who has a strong family and then personal history of cancer. In parallel, the movie follows the decades of research by Dr. Mary-Claire King and her team on their road to discovering the BRCA1 gene.

We blog about the BRCA1 and the related BRCA2 genes regularly, but as a refresher—certain mutations in these genes lead to an increased risk to develop breast and ovarian cancer, among other cancer types. Additionally, BRCA1/2 mutations can be passed down from parents to offspring, and the chance of having a BRCA1/2 mutation is ten-fold greater in individuals of Ashkenazi Jewish descent than it is in the general population. BRCA “status” can be revealed by genetic testing, and BRCA mutation “carriers” have medical management options available to them for reducing the risk of developing cancers or for detecting cancers at a very early (and perhaps treatable) stage if they do develop.

It was my second time seeing the movie, and also my second time crying through it. But this time I also watched it with different eyes, since our Program has gotten more and more involved in the BRCA education and testing realms over the past two years. We talk and talk about the importance of knowing and discussing one’s family medical history. Even in the 1970s, before the concept of hereditary cancer predisposition syndromes existed, Annie Parker (and undoubtedly others like her) had the gut feeling that cancer was running in her family and that it was always lurking in the shadows, waiting to get her. And this caused Annie to live in constant fear and to obsess over things like breast self-exams, library searches, and diets.

In our times, we are fortunate to have the genetic knowledge about the implications of familial BRCA1/2 mutations and the ability to test for carrier status and to guide those who are identified as carriers. While being Ashkenazi Jewish is in and of itself a risk factor for carrying a BRCA mutation, this risk factor is exacerbated by having a family history of BRCA-related cancers. Under current guidelines from the National Comprehensive Cancer Network, being Ashkenazi Jewish and having a first or second degree blood relative (meaning a parent, child, sibling, grandparent, grandchild, aunt/uncle or niece/nephew) who has had breast, ovarian or pancreatic cancer at any age would warrant pursuing BRCA testing (along with genetic counseling). Many of us probably fall into that category but don’t realize what this may connote.

Getting back to the movie and all those tears—it’s been a really busy summer at the PJGH so far, and it was definitely a welcome change of pace to have “PJGH movie in the morning.” It was also really powerful and authentic have a good “group cry.” I think the whole experience reinforced our joint commitment to protecting the genetic health of the Jewish community and its future generations. But I still need to think about why the team is rallying for seeing Pitch Perfect together next.

PS The movie we saw (at work) was pretty graphic on multiple levels–consider yourselves warned…

Are we sure we really want to go there?

DNA code analysisAs an Ashkenazi Jew and someone who was pregnant several times in the late 1990s and early 2000s, I witnessed, from the perspective of a patient, the stepwise increase in the number of Jewish genetic diseases for which carrier testing was available.  When I moved into this scientific realm professionally in 2006, I realized that that was only the tip of the iceberg.  What had started out as population testing for one disease only (Tay-Sachs) in the 1970s rapidly advanced gene-by-gene, to the point where now we readily can test for carrier status for at least 18 of the so-called “Ashkenazi Jewish genetic diseases.”

Until recently, testing was performed in a gene by gene manner, resulting in additive costs that reached the thousands of dollars.  Fortunately, breakthroughs in technology have led to significant progress in reducing the costs associated with screening for many diseases at the same time.   Now, a single DNA sample can be assessed on a “chip” or an “array” that simultaneously can survey many mutations in many disease genes .  If a mutation is detected by the array, then that individual is said to be a “carrier” of the associated genetic disease.  Remember, carriers themselves do not and will not exhibit symptoms of that disease, but offspring of carrier couples are at risk to be affected.

Okay, now here is where the “are we sure we really want to go there” question comes into play.  Right now, we are still testing for the common mutations in the relevant disease genes with these “targeted” arrays.  But there are other rarer mutations in those same genes that have been described to be disease-associated that are not being assessed routinely. So, some carriers are being missed.    If we wanted to look at each disease gene in its entirety, we could instead be using a technology called gene sequencing.  With gene sequencing, each position in the gene is “read” and then cross-compared to the normal sequence.  Many companies and laboratories are thinking about/developing sequencing platforms for the purpose of carrier identification, with the goal of missing fewer carriers.

So what’s the downside? The downside is that we will not only pick up the common+rarer disease mutations, but we will also pick up changes that we cannot interpret properly because we have not seen them before (these changes are called “variants of unknown significance”).  They could be disease-causing in offspring of carrier couples, but alternatively they could be benign.  If we as professionals can’t interpret these properly, what do we tell the patients?

And you know what makes me even more anxious? The alternative concept of sequencing ALL of someone’s genes (their genome) for carrier identification, as opposed to just focusing the sequencing on a targeted subset of genes, such as the subset that causes the Ashkenazi Jewish diseases.  In that scenario, not only will we be grappling with the variants of unknown clinical significance, but also with findings throughout the genome that are incidental/unanticipated. These findings could include mutations that lead to adult-onset disease in the carriers themselves, some of which diseases have no treatments or cures.

Only time will tell where the field is heading, and advances in technology coupled with decreasing costs may be the ultimate drivers here.  I think we should pause and think about how vast the ocean is before taking the plunge.

Thinking Outside the Lines


A few weeks ago, Emily, one of my fellow genetic counselors, saw an Ashkenazi Jewish young woman and her mother for counseling. The reason for their visit was because the mother has a BRCA mutation, which means that she carries a genetic mutation which dramatically increases her risk to develop breast and ovarian cancer. It also means that each of her children has a 50% risk of inheriting the same mutation.

As in any genetic counseling session, Emily took a detailed family history. Her questioning led her to learn some new facts about the young woman: she was only half Ashkenazi, and she and her husband had already done some carrier screening for common diseases in the Ashkenazi population that could affect offspring a few years earlier, and were found to be genetically ‘compatible.’  Emily recommended that she update her panel, despite her only being half Ashkenazi, since she was not tested for the whole battery of tests that is available today. The thought of updating had never crossed her mind. The young woman also had BRCA testing on that day, which at the time, was more anxiety-provoking since its potential results carried more ramifications to her own health.

About 2 weeks later, the results were in. It turns out she was a carrier for 3 ”Ashkenazi Jewish” diseases that she was not tested for earlier! A triple carrier! Had Emily not taken the time to take the family history and think about things that were beyond what the patient came to talk about, this may have not been picked up. This story has a happy ending –the young woman was negative for the BRCA mutation (phew!) and her husband tested negative for all 3 diseases.  But unfortunately it does not always end this well.

Emily’s story makes me want to remind you that genetic information can be difficult to sort through. That is why I am encouraging you to have a genetic counselor explain it all in English and make sure all the proper testing is ordered.  Thinking outside the lines comes with proper training and therefore, if you have any concerns about your genetic health, I strongly encourage you to seek professional help in this realm. You never know.

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