Advances in the Genetics of Alzheimer’s Disease at AAIC 2017

Posted By: Timothy J. Hohman, Assistant Professor of Neurology, Vanderbilt Memory & Alzheimer’s Center

I just returned from the Alzheimer’s Association International Conference (AAIC) in London. AAIC always covers an amazing breadth of the most recent advances in research and clinical care for Alzheimer’s Disease (AD), and this year placed a particular emphasis on biomarkers. More specifically, the focus was on how we can integrate the growing availability of in vivo biomarkers of AD neuropathology into diagnostic criteria for research, and into screening procedures for clinical trials.

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Timothy J. Hohman, PhD (courtesy Dr. Hohman)

The Potential of Biomarkers

Philip Scheltens, MD, PhD, from the VU University Medical Center in the Netherlands kicked off the meeting with an impassioned lecture on the present landscape of biomarkers in AD, and the future potential of biomarkers in screening, diagnosis, targeted treatments, and disease prevention. AD is characterized by two primary neuropathologies: extracellular plaques composed of the amyloid-β protein and neurofibrillary tangles composed of hyper-phosphorylated tau. Over the past ten years, there has been a growing emphasis on measuring these proteinopathies in vivo, including the development of positron emission tomography tracers for amyloid and tau, and the development of assays to measure these proteins in cerebrospinal fluid. In 2011, the National Institute on Aging and the Alzheimer’s Association convened four work groups to develop new research criteria for diagnosis that integrated biomarkers of amyloid deposition into the clinical criteria for dementia. This year’s conversations focused on taking steps towards diagnosis and screening that relied solely on biomarkers.

Dr. Schelten’s emphasis on the future of biomarkers set up a somewhat heated panel presentation laying out a new NIA-AA research framework to investigate Alzheimer’s disease. Led by Clifford Jack, MD, the proposed framework would place a greater emphasis on biomarkers of the two primary proteinopathies, while also emphasizing the measurement and characterization of neurodegeneration. The panel has provided the opportunity for the community to give feedback directly to the workgroup as they continue to refine the proposed framework. Certainly, this will be a critical issue in AD research in the coming year and has important implications for clinical trials, study design, and (eventually) clinical care.

Functional Pathways, GWAS Findings, and AD

This is a genetics blog, though, so let’s get into the genetics! The primary keynote session on the genetics of AD was given by Julie Williams, PhD, from Cardiff University. Dr. Williams provided an overview of where we currently stand in unraveling the genetic architecture of the disease, and called for an increased emphasis on uncovering functional pathways that underlie the known risk loci. Dr. Williams argued the innate immunity and inflammation are fundamental pathways in AD pathogenesis, and that the causal pathways of sporadic AD may be fundamentally distinct from familial forms that operate strictly through an amyloid pathway.

Research presented throughout the conference re-emphasized the importance of innate immunity, including new risk loci in common variant and rare variant analyses completed by the Alzheimer’s Disease Genetics Consortium that implicated innate immune pathways (e.g., LILRA5).  Additionally, many of the functional genomic approaches emphasized the importance of macrophage and monocyte expression in predicting AD, including 14 genes implicated in a genetically regulated transcriptomic analysis by Towfique Raj, PhD, from the Icahn School of Medicine.

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Data parasites and data philanthropists both have important roles to play in using big data to study Alzheimer’s. (courtesy Dr. Hohman)

Given the growing emphasis on biomarkers throughout the field of AD, it was also encouraging to see substantial growth in the size of endophenotype analyses, including a GWAS of cerebrospinal fluid biomarkers of AD by Yuetiva Deming, PhD, analyzing data from over 3,000 individuals. Simon Lovestone, PhD, gave an additional “big data” plenary lecture in which he laid out how large-scale European collaborations integrating electronic medical record data and other big data resources will change the way research is completed. He called on #DataParasites (those who perform secondary analyses on existing datasets) to make use of rich data resources to identify new treatment targets and #DataPhilanthropists (data providers) to continue to step up and provide open access to collected data. Large scale data collection, data sharing, and secondary data analysis are becoming central components of AD research.

Varied Approaches to #EndALZ

There were many other areas of focus: from advances in neuroimaging and large-scale omics, to a growing emphasis on sex differences, racial disparities, and pathways of resilience, and a growing acceptance of the heterogeneity in the neuropathological presentation of the disease. If you are interested in AD and want to learn more from a variety of perspectives, this is a fantastic conference to attend. The field of AD is necessarily interdisciplinary and this conference is a fantastic representation of that diversity. Multiple perspectives, approaches, and treatment pathways will be needed to beat this devastating disease. After another year and another great conference, I’m hopeful and inspired to keep working to #EndALZ. Join us!

Timothy J. Hohman, PhD, is an Assistant Professor of Neurology at the Vanderbilt Memory & Alzheimer’s Center. He has been part of the ASHG community since 2013.

Teens’ Nuanced Views about Genetic Testing, at ESHG 2017

Posted by: Michael Dougherty, PhD, ASHG Director of Education

What do adolescents think about genetic testing – in particular, clinical recommendations to defer genetic testing for adult-onset conditions? We are beginning to have an answer, thanks to a research collaboration involving ASHG, Geisinger, and Sarah Lawrence College. Late last month, I had the opportunity to present our initial analysis at the 2017 European Human Genetics Conference (ESHG 2017) in Denmark.

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Nyhavn waterfront, Copenhagen, Denmark. (Credit: Michael Dougherty)

First, for those who haven’t been to Copenhagen, it’s a beautiful city that I highly recommend. Deep history, friendly people (almost all of whom speak excellent English), and the convenient mass transit that is so typical of Europe. Walk along the canals or climb the external staircase to the top of Vor Frelser’s Kirke (Our Savior’s Church). An hour north of Copenhagen, Kronborg Castle, which is the model for Shakespeare’s Elsinore in Hamlet, is an especially nice day trip. If you’re adventurous, try the Danish national meal, ‘stegt flæsk,’ a delicious crispy pork dish, which came with the following warning in our restaurant’s menu: “Ask your waiter before ordering”! But now, back to the research.

Little is known about how adolescents view genetic testing, especially the psychosocial impacts of the benefits and harms frequently discussed by experts, yet clinical practice often involves decisions that may affect them. Our research used data from ASHG’s annual DNA Day Essay Contest entries to characterize adolescents’ views.

ASHG’s 2016 DNA Day Essay Contest question asked high school students to identify an adult-onset genetic condition and to defend or refute the recommendation in ASHG’s 2015 position statement to defer genetic testing until adulthood. Over 1,200 essays from 45 U.S. states and 22 non-U.S. countries were assessed using thematic, mixed-methods analysis. Students identified 100 conditions, but 75% chose one of five more familiar disorders, including Huntington disease, hereditary breast and ovarian cancer (e.g., BRCA), and Alzheimer’s. Across all conditions, roughly equal numbers of students chose to defer testing as to not defer.

We then dug deeper to examine students’ choices regarding specific conditions, such as testing for a BRCA predisposition to breast and ovarian cancer (BRCA) and for Alzheimer’s disease (AD), which differ considerably in medical actionability. Here some statistically significant differences began to emerge. With AD, nearly two-thirds of students chose to defer testing, whereas with BRCA, fewer than half chose to defer.

The reasons students gave to justify their decisions were sophisticated and often matched those reflected in clinical guidelines and ethical discussions. Reasons to defer often included risk of psychological harm to the minor or the uncertainty of predictions arising from test results (e.g., ApoE4). Reasons not to defer included the benefits of alleviating uncertainty and preparing for increased surveillance (e.g., early, regular mammograms).

The rich data provided in the students’ essays will be mined for additional insights that may inform the development of future recommendations, but even now it appears clear that the decisions of mature adolescents should be taken seriously by clinicians.

Michael J. Dougherty, PhD, is Director of Education at ASHG. This research collaboration’s work was presented at ESHG 2017 as a poster and featured in the meeting’s Best Posters Session.

Reflecting on APHMG 2017

Posted by: Kathryn Garber, PhD, Chair of the ASHG Communications Committee

I’m just back from the annual meeting of the Association of Professors of Human and Medical Genetics (APHMG), and, as always, my head is swimming with ideas. For those not familiar with APHMG, it is a group that promotes human and medical genetics education in graduate and medical schools across North America. It’s a meeting where we spend most of our time talking about teaching and learning, but the fact that we are all geneticists means that we have a common understanding of the science we need to teach. We also discuss more practical issues of program design and oversight, particularly for medical students, residents and fellows.

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APHMG 2017 attendees take a break from presentations for a pirate ship excursion. (courtesy Dr. Garber)

The focus of this year’s meeting was adult learning. Hope Ricciotti from Beth Israel Deaconess Hospital kicked things off with some valuable hints on interacting with millennial learners, including ideas on how to structure feedback to members of the “trophy generation”, who often aren’t used to negative feedback. Kadriye Lewis from Children’s Mercy Hospital in Kansas City then put adult learning in perspective through illustrations of different learning theories and their implementation. Next, Sarah Farrell and members of her team from Apple Education demonstrated tools and resources for use in education, including eBooks and courses that can be created or used by faculty, and apps that can foster interactivity in the classroom.

The second day of the meeting had a scientific focus on big data. Mike Murray from Geisinger described their approach to return of results to participants in their population-based GenomeFIRST project. He was followed by Sarah Elsea from Baylor, who discussed the use of large scale metabolomic profiles to identify inborn errors of metabolism. Finally, Piero Rinaldo from the Mayo Clinic argued passionately that we should stop using reference cutoffs to interpret biomarkers for metabolic disease, and should replace this approach with an assessment of the likelihood that an individual’s biomarker profile is more consistent with a normal or disease profile, based on large numbers of previously tested samples.

As usual, the annual meeting also included workshops by three special interest groups (SIGs), each one focused on a different set of trainees: medical genetics residents, medical students, and clinical laboratory fellows. I attended the medical student education workshop, which this year was co-sponsored by the Association of Biochemistry Educators (ABE). This allowed us to focus on topic integration across the undergraduate medical curriculum, and we had a productive small group session in which biochemists and geneticists worked together to develop teaching cases that integrate the two subjects. Later in the day, we brainstormed the inclusion of ethics in integrated medical curricula, as well as approaches to bringing the basic sciences into the clinical curriculum.

For me – and I think for many others – the most valuable part of the APHMG meeting is getting to know people who are teaching genetics at medical schools and hospitals across the country. We share ideas, create materials together, and establish collaborative projects that continue throughout the year. One of the key products of these interactions in recent years has been the sharing of resources that can be used broadly within the SIGs, including cases, assessments, evaluations, competency frameworks, and curricula. The Genetics Education Resource Exchange houses a number of these resources focused on undergraduate medical education. If your institution is an APHMG member, you can access this valuable resource. (Full disclosure: I was a member of the group that initiated this resource and was the founding curator of the resource exchange, a job that now belongs to Andrew Sobering from St. George’s University.)

If you want to meet and learn from people who are passionate about genetics education, this is the place, and I encourage you to join this supportive and collaborative group at our meeting in Santa Fe next spring. As you can see in the picture of our pirate ship excursion, we also make time for fun. Now, I’m off to take all of the great ideas that were sparked at the meeting and work on my syllabus for next semester.

Kate Garber, PhD, is an Associate Professor at Emory University. She is involved in designing and implementing human genetics training for physician assistants, genetic counselors, and medical students. Read more about Kate’s career.

A Genetic Counselor’s Perspective of ACMG 2017

Posted by Karen Hanson, MS, MBA, CGC, Health Professional Education Programs Manager at ASHG

Last month, I had the opportunity to attend the American College of Medical Genetics and Genomics (ACMG) 2017 Annual Meeting. As a genetic counselor working on health professional education at ASHG, one theme stood out to me: the rapid integration of whole genome/exome sequencing (WGS/WES) into clinical practice.

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Karen Hanson (right) and Director of Education Michael Dougherty, at the ASHG booth in the ACMG Exhibit Hall.

Apparently, we are sequencing everyone – sick people, healthy people, adults, children, babies, and fetuses. The inspiring talk by William Gahl, MD, PhD, NHGRI, NIH about the work of the Undiagnosed Diseases Network (UDN) reminded us all of why we (researchers, clinicians, laboratorians) entered this field. This session showcased what could be thought of as the most traditional use of WGS/WES in the clinic: using advances in genomic sequencing to improve diagnostic outcomes in patients with suspected genetic disease. It’s now less likely that patients and families will struggle without a diagnosis for years.

Infants born with congenital anomalies or metabolic disease are also benefiting from rapid sequencing technologies that allow their physicians and families to quickly treat and manage them. And it’s not just ‘sick’ babies that are being offered sequencing. Several clinical trials are looking at the efficacy and outcomes of sequencing ‘healthy’ newborns. For years, the genetics community has talked about when the day would come that all newborns have a ‘genetic’ barcode (consider that the movie Gattaca turns 20 this year!). Newborn screening programs have already expanded to include dozens of carefully selected disorders, and WES almost seems like a logical next step. However, in at least in one clinical trial, the majority of parents of healthy newborns who were offered WES declined testing. So maybe we are not quite ready yet.

Another session was devoted to genomic sequencing in ‘healthy’ adults. The current scientific atmosphere certainly seems right for this, when you consider the advances in sequencing technology, the rapid growth of variant databases, and the push for personalized medicine. It did occur to me that we haven’t really worked out the ethical and logistics dilemmas we encounter through WGS/WES of ‘unhealthy’ individuals. However, to paraphrase Les Biesecker, MD, FACMG, NHGRI, genome sequencing is here and it’s not going away. The dilemmas associated with sequencing ‘healthy’ people are not new – variant classification, not enough genetic professionals, health provider education, and access to diverse and underserved populations. But overall, the intention is good – to use genomic technology to improve health and patient care. Which for me begs at least one question: who’s going to manage all these ‘patients’? After all, we will all be ‘patients’ after we get our WGS test results.

So, as a genetic counselor working on health professional education at ASHG, I think of all this as job security. My job – our job as geneticists – is cut out for us. We need to educate our medical workforce and all the rest of the ‘patients’ out there about genomic medicine. And who better to do it then those of us who have been and still are in the trenches.

Karen Hanson, MS, MBA, CGC, is Health Professional Education Programs Manager at ASHG. Read more about ASHG’s educational programs for health professionals.