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Williams, Marc S

0000-0001-6165-8701

Mayo Clinic

Department of Genomic Health, Geisinger, 100 N. Academy Ave., Danville, PA, 17822, USA

Citations 22

COMPREHENSIVE GENETIC INVESTIGATION REVEALS HETEROGENEOUS PATHWAYS TO OBSTRUCTIVE SLEEP APNEA
Justice, Anne E. , Pahl, Matthew C. , Gupta, Shreyash , Kim, Soriul , Thorleifsson, Gudmar, Gutierrez, Alejandro , Oliveira, Fernando Andrade de , Ackert‐Bicknell, Cheryl L. , Benediktsdottir, Bryndis, Boero, Jaime, Borthwick, Kenneth M., Chen, N., Cistulli, Peter A. , Favazzo, Lacey J. , Gottlieb, Daniel J. , Hakonarson, H., Kirchner, H. Lester , Mazzotti, Diego R, Mentch, Frank , Morgentheler, Timothy I, Penzel, Thomas, Pippin, James A. , Rasmussen-Torvik, Laura J, Shin, Chol, Singh, Bhajan, Sofer, T., Villani, David A. , Wells, Andrew D, Zee, Phyllis, Jonsdottir, Ingileif, Gislason, Thorarinn, Robishaw, Janet, Stefansson, K., Grant, Struan FA., Pack, A., Þorleifsson, Guðmar , Kim, Soriul , Thorleifsson, Gudmar , Manduchi, Elisabetta , Gutierrez, Alejandro , Cistulli, Peter A , Gottlieb, Daniel J , Magalang, Ulysses J , Mazzotti, Diego R , Mentch, Frank D , Morgenthaler, Timothy I , Rasmussen-Torvik, Laura J , Shin, Chol , Singh, Bhajan , Sofer, Tamar , Williams, Marc S , Zuscik, Michael J , Jonsdottir, Ingileif , Gislason, Thorarinn , Stefánsson, Kári , Keenan, Brendan T , Chittoor, Geetha , Hoskens, Hanne , Josyula, Navya Shilpa , Oliveira, Fernando Andrade, Malow, Beth A. , McArdle, Nigel , Morgenthaler, Timothy I. , Penzel, Thomas , Sofer, Tamar , Veatch, Olivia J. , Robishaw, Janet D. , Stefánsson, Kāri , Grant, Struan F.A. , Hallgrímsson, Benedikt , Pack, Allan I

No container title available | January 11, 2026 | Volume: No volume available | Issue: No issue available | Pages: No page available

10.64898/2026.01.08.26343696 Get It

ABSTRACT Obstructive sleep apnea (OSA) is a common, heritable disorder with diverse clinical presentations and etiologies. We conducted a genome-wide association meta-analysis of 492,107 individuals, including 46,028 OSA cases, identifying 14 genome-wide significant loci, eight of which are novel. Analyses adjusting for body mass index (BMI) revealed three loci independent of obesity, implicating alternative biological pathways contributing to disease. Integrative functional analyses, including chromatin interaction mapping, fine-mapping, and eQTL colocalization, prioritized candidate effector genes. Notably, implicated genes in chondrocytes were associated with craniofacial morphology in both mouse and human multivariate genotype-phenotype mapping, supporting a role for craniofacial structure in OSA risk. These findings highlight key genetic pathways (obesity-related, neurological, and craniofacial) underlying the development of OSA, offering new insights into its complex etiology.
Genomic Screening at a Single Health System
Savatt, Juliann M. , Sturm, Amy C. , McCormick, Cara Z., Nixon, Michelle Pistner , Rolston, David D.K. , Wain, Karen E. , Willard, Huntington F. , Faucett, W. Andrew , Ledbetter, David H., Buchanan, Adam H. , Martin, Christa L., Strande, Natasha T. , Sturm, Amy C , Kelly, Melissa , Williams, Marc S , Martin, Christa L.

JAMA Network Open | March 17, 2025 | Volume: 8 | Issue: 3 | Pages: e250917

10.1001/jamanetworkopen.2025.0917 Get It

Importance Completion of the Human Genome Project prompted predictions that genomics would transform medicine, including through genomic screening that identifies potentially medically actionable findings that could prevent disease, detect it earlier, or treat it better. However, genomic screening remains anchored in research and largely unavailable as part of routine care. Objective To summarize 11 years of experience with genomic screening and explore the landscape of genomic screening efforts. Design, Setting, and Participants This cohort study was based in Geisinger’s MyCode Community Health Initiative, a genomic screening program in a rural Pennsylvania health care system in which patient-participants exomes are analyzed. Main Outcomes and Measures Genomic screen-positive rates were evaluated and stratified by condition type (cancer, cardiovascular, other) and US Centers for Disease Control and Prevention (CDC) Tier 1 designation. The proportion of participants previously unaware of their genomic result was assessed. Other large-scale population-based genomic screening efforts with genomic results disclosure were compiled from public resources. Results A total of 354 957 patients participated in Geisinger’s genomic screening program (median [IQR] age, 54 [36-69] years; 194 037 [59.7%] assigned female sex at birth). As of June 2024, 175 500 participants had exome sequencing available for analysis, and 5934 participants (3.4%) had a pathogenic variant in 81 genes known to increase risk for disease. Between 2013 and July 2024, 5119 results were disclosed to 5052 eligible participants, with 2267 (44.2%) associated with risk for cardiovascular disease, 2031 (39.7%) with risk for cancer, and 821 (16.0%) with risk for other conditions. Most results (3040 [59.4%]) were in genes outside of those with a CDC Tier 1 designation. Nearly 90% of participants (4425 [87.6%]) were unaware of their genomic risk prior to disclosure. In a survey of large-scale biobanks with genomic and electronic health record (EHR) data, only 25.0% (6 of 24) disclosed potentially actionable genomic results. Conclusions and Relevance In this large, genomics-informed cohort study from a single health system, 1 in 30 participants had a potentially actionable genomic finding. However, nearly 90% were unaware of their risk prior to screening, demonstrating the utility of genomic screening in identifying at-risk individuals. Most large-scale biobanks with genomic and EHR data did not return genomic results with potential medical relevance, missing opportunities to significantly improve genomic risk ascertainment for these individuals and to perform longitudinal studies of clinical and implementation outcomes in diverse settings.
Enabling the clinical application of artificial intelligence in genomics: a perspective of the AMIA Genomics and Translational Bioinformatics Workgroup
Walton, Nephi , Nagarajan, Radha, Wang, Chen , Sincan, Murat , Everman, David B. , Walton, Derek C, Alekseyenko, Alexander V. , Song, Qianqian , Uzun, Ece D. Gamsiz , Taylor, Casey Overby , Uzun, Alper , Person, Thomas N., Benos, Panayiotis V , Alekseyenko, Alexander V , Song, Qianqian , Rappoport, Nadav , Zhao, Zhongming , Wang, Chen , Gamsiz Uzun, Ece D , Nagarajan, Radha , Freimuth, Robert R. , McGrath, Scott , Lemas, Dominick J. , Williams, Marc S

Journal of the American Medical Informatics Association | December 1, 2023 | Volume: 31 | Issue: 2 | Pages: 536-541

10.1093/jamia/ocad211 Get It

Abstract Objective Given the importance AI in genomics and its potential impact on human health, the American Medical Informatics Association—Genomics and Translational Biomedical Informatics (GenTBI) Workgroup developed this assessment of factors that can further enable the clinical application of AI in this space. Process A list of relevant factors was developed through GenTBI workgroup discussions in multiple in-person and online meetings, along with review of pertinent publications. This list was then summarized and reviewed to achieve consensus among the group members. Conclusions Substantial informatics research and development are needed to fully realize the clinical potential of such technologies. The development of larger datasets is crucial to emulating the success AI is achieving in other domains. It is important that AI methods do not exacerbate existing socio-economic, racial, and ethnic disparities. Genomic data standards are critical to effectively scale such technologies across institutions. With so much uncertainty, complexity and novelty in genomics and medicine, and with an evolving regulatory environment, the current focus should be on using these technologies in an interface with clinicians that emphasizes the value each brings to clinical decision-making.
Abstract 10822: Familial Hypercholesterolemia in the EMERGE Network: 1-Year Outcomes After Return of Results
Kochan, David C., Perez, Emma , Anderson, Katherine , Salvati, Zachary , Hebbring, Scott J. , Gibbs, Richard A. , Linder, Jodell E. , Roden, Dan M. , Manolio, Teri A. , Sherafati, Alborz , Dikilitas, Ozan , Saadatagah, Seyedmohammad , Satterfield, Benjamin A. , Jones, Laney K , Sharp, Richard R. , Sturm, Amy C. , Zouk, Hana , Venner, Eric , Chung, Wendy K. , Peterson, Josh F. , Jarvik, Gail P. , Rehm, Heidi L. , Roden, Dan M. , Williams, Marc S , Kullo, Iftikhar J.

Circulation | June 15, 2023 | Volume: 146 | Issue: Suppl_1 | Pages: No page available

10.1161/circ.146.suppl_1.10822 Get It

Introduction: Relatively little is known about outcomes following return of secondary findings detected in large scale sequencing projects. We assessed 1-year outcomes following return of pathogenic/likely pathogenic (P/LP) variants associated with familial hypercholesterolemia (FH) in phase III of the eMERGE network (2015-2019). Methods: Adult participants (n=18,544) at 7 sites were enrolled in a prospective cohort study to study the clinical impact of returning results from targeted sequencing of 68 actionable genes, including LDLR , APOB , and PCSK9 . Process, intermediate, and/or clinical outcomes within 1-year after return of results (RoR) were ascertained by electronic health record (EHR) review. A process outcome was defined as referral to a specialist or ordering new tests, including lipid profile and screening tests for coronary heart disease. An intermediate outcome was defined as new diagnosis of FH or atherosclerotic cardiovascular disease. A clinical outcome was defined as initiation or change in lipid-lowering medication. The primary outcomes were a new diagnosis of FH and modification of lipid lowering therapy. Results: Results were returned to 134 individuals, and data for 119 participants were available for the outcomes analysis. Process (86%), intermediate (49%), and/or clinical (26%) outcomes occurred in 92% of participants. Process outcomes included 72% with new tests ordered and 61% referred to a specialist. Before RoR, 86.5% of individuals with FH associated P/LP variants had a diagnosis of hypercholesterolemia but only 17.6% had a diagnosis of FH; 89% were on a statin but only 58% were on a high intensity statin. Following RoR, 44% (52/119) received a new diagnosis of FH. Lipid lowering treatment was modified in 26% (31/119), including initiation of a statin in 5%, increasing statin dose in 13%, and adding ezetimibe or a PCSK9 inhibitor in 12.6%. Conclusions: In a multisite cohort of EHR-linked biobanks, monogenic FH was underdiagnosed (only 17.6% had a specific diagnosis) and undertreated (only 58% were on a high intensity statin); 44% of participants received a new diagnosis of FH and 26% had lipid lowering treatment modified after RoR. These results highlight the clinical utility of returning FH variants in EHR-linked biobanks.
Familial Hypercholesterolemia in the Electronic Medical Records and Genomics Network: Prevalence, Penetrance, Cardiovascular Risk, and Outcomes After Return of Results
Dikilitas, Ozan , Sherafati, Alborz , Saadatagah, Seyedmohammad , Kochan, David C., Anderson, Katherine , Chung, Wendy K. , Hebbring, Scott J. , Salvati, Zachary , Sharp, Richard R. , Sturm, Amy C. , Gibbs, Richard A. , Rowley, Robb , Linder, Jodell E. , Perez, Emma , Peterson, Josh F. , Jarvik, Gail P. , Roden, Dan M. , Manolio, Teri A. , Satterfield, Benjamin A , Anderson, Katherine C , Chung, Wendy K. , Salvati, Zachary M , Sharp, Richard R , Sturm, Amy C , Rowley, Robb , Venner, Eric , Linder, Jodell E , Jones, Laney K , Peterson, Josh F , Jarvik, Gail P , Rehm, Heidi L , Zouk, Hana , Roden, Dan M. , Williams, Marc S , Manolio, Teri A , Kullo, Iftikhar J , Dikilitas, Ozan , Satterfield, Benjamin A. , Venner, Eric , Rehm, Heidi L. , Kullo, Iftikhar J.

Circulation: Genomic and Precision Medicine | February 22, 2023 | Volume: 16 | Issue: 2 | Pages: No page available

10.1161/circgen.122.003816 Get It

Background: The implications of secondary findings detected in large-scale sequencing projects remain uncertain. We assessed prevalence and penetrance of pathogenic familial hypercholesterolemia (FH) variants, their association with coronary heart disease (CHD), and 1-year outcomes following return of results in phase III of the electronic medical records and genomics network. Methods: Adult participants (n=18 544) at 7 sites were enrolled in a prospective cohort study to assess the clinical impact of returning results from targeted sequencing of 68 actionable genes, including LDLR , APOB , and PCSK9 . FH variant prevalence and penetrance (defined as low-density lipoprotein cholesterol >155 mg/dL) were estimated after excluding participants enrolled on the basis of hypercholesterolemia. Multivariable logistic regression was used to estimate the odds of CHD compared to age- and sex-matched controls without FH-associated variants. Process (eg, referral to a specialist or ordering new tests), intermediate (eg, new diagnosis of FH), and clinical (eg, treatment modification) outcomes within 1 year after return of results were ascertained by electronic health record review. Results: The prevalence of FH-associated pathogenic variants was 1 in 188 (69 of 13,019 unselected participants). Penetrance was 87.5%. The presence of an FH variant was associated with CHD (odds ratio, 3.02 [2.00–4.53]) and premature CHD (odds ratio, 3.68 [2.34–5.78]). At least 1 outcome occurred in 92% of participants; 44% received a new diagnosis of FH and 26% had treatment modified following return of results. Conclusions: In a multisite cohort of electronic health record–linked biobanks, monogenic FH was prevalent, penetrant, and associated with presence of CHD. Nearly half of participants with an FH-associated variant received a new diagnosis of FH and a quarter had treatment modified after return of results. These results highlight the potential utility of sequencing electronic health record–linked biobanks to detect FH.
A research agenda to support the development and implementation of genomics-based clinical informatics tools and resources
Wiley, Ken, Findley, Laura, Goldrich, Madison P., Rakhra-Burris, Tejinder, Stevens, Ana, Bult, Carol J. , Deverka, Patricia A. , Green, Eric D. , Jarvik, Gail P. , Ramos, Erin M. , Relling, Mary V. , Roden, Dan M. , Rowley, Robb , Alterovitz, Gil , Aronson, Samuel , Bastarache, Lisa , Jeff, Janina M., Madhavan, Subha , Mendonça, Eneida A. , Ohno‐Machado, Lucila , Ritchie, Marylyn D. , Walton, Nephi , Zayas‐Cabán, Teresa, Manolio, Teri A. , Bult, Carol J , Roden, Dan M. , Cimino, James J , Del Fiol, Guilherme , Hoffman, Mark A , Kawamoto, Kensaku , Jarvik, Gail P , Williams, Pamela, Chisholm, Rex L. , Ginsburg, Geoffrey S. , Mensah, George A. , Cimino, James J. , Crowgey, Erin L. , Fiol, Guilherme Del , Freimuth, Robert R. , Hoffman, Mark A. , Johnson, Kevin B. , Pratap, Siddharth , Taylor, Casey Overby , Weng, Chunhua , Williams, Marc S

Journal of the American Medical Informatics Association | April 14, 2022 | Volume: 29 | Issue: 8 | Pages: 1342-1349

10.1093/jamia/ocac057 Get It

Abstract Objective The Genomic Medicine Working Group of the National Advisory Council for Human Genome Research virtually hosted its 13th genomic medicine meeting titled “Developing a Clinical Genomic Informatics Research Agenda”. The meeting’s goal was to articulate a research strategy to develop Genomics-based Clinical Informatics Tools and Resources (GCIT) to improve the detection, treatment, and reporting of genetic disorders in clinical settings. Materials and Methods Experts from government agencies, the private sector, and academia in genomic medicine and clinical informatics were invited to address the meeting's goals. Invitees were also asked to complete a survey to assess important considerations needed to develop a genomic-based clinical informatics research strategy. Results Outcomes from the meeting included identifying short-term research needs, such as designing and implementing standards-based interfaces between laboratory information systems and electronic health records, as well as long-term projects, such as identifying and addressing barriers related to the establishment and implementation of genomic data exchange systems that, in turn, the research community could help address. Discussion Discussions centered on identifying gaps and barriers that impede the use of GCIT in genomic medicine. Emergent themes from the meeting included developing an implementation science framework, defining a value proposition for all stakeholders, fostering engagement with patients and partners to develop applications under patient control, promoting the use of relevant clinical workflows in research, and lowering related barriers to regulatory processes. Another key theme was recognizing pervasive biases in data and information systems, algorithms, access, value, and knowledge repositories and identifying ways to resolve them.
Infobuttons for Genomic Medicine: Requirements and Barriers
Connolly, John J. , Pet, Douglas , Peterson, Josh F. , Shirts, Brian H. , Starren, Justin , Walton, Nephi , Connolly, John J , Peterson, Josh F , Rasmussen, Luke V. , Fiol, Guilherme Del , Freimuth, Robert R. , Williams, Marc S , Taylor, Casey Overby

Applied Clinical Informatics | May 12, 2021 | Volume: 12 | Issue: 02 | Pages: 383-390

10.1055/s-0041-1729164 Get It

Abstract Objectives The study aimed to understand potential barriers to the adoption of health information technology projects that are released as free and open source software (FOSS). Methods We conducted a survey of research consortia participants engaged in genomic medicine implementation to assess perceived institutional barriers to the adoption of three systems: ClinGen electronic health record (EHR) Toolkit, DocUBuild, and MyResults.org. The survey included eight barriers from the Consolidated Framework for Implementation Research (CFIR), with additional barriers identified from a qualitative analysis of open-ended responses. Results We analyzed responses from 24 research consortia participants from 18 institutions. In total, 14 categories of perceived barriers were evaluated, which were consistent with other observed barriers to FOSS adoption. The most frequent perceived barriers included lack of adaptability of the system, lack of institutional priority to implement, lack of trialability, lack of advantage of alternative systems, and complexity. Conclusion In addition to understanding potential barriers, we recommend some strategies to address them (where possible), including considerations for genomic medicine. Overall, FOSS developers need to ensure systems are easy to trial and implement and need to clearly articulate benefits of their systems, especially when alternatives exist. Institutional champions will remain a critical component to prioritizing genomic medicine projects.
Loci identified by a genome‐wide association study of carotid artery stenosis in the eMERGE network
Palmer, Melody R. , Kim, Daniel Seung , Crosslin, David R. , Stanaway, Ian B. , Rosenthal, Elisabeth A. , Cronkite, David , Gordon, Allan , Du, Xiaomeng, Li, Yatong K., Feng, QiPing , Li, Rongling, Håkonarson, Håkon , Fasel, David , Sohn, Sunghwan , Sleiman, Patrick , Handelman, Samuel K. , Speliotes, Elizabeth K. , Larson, Eric B. , Jarvik, Gail P. , Jarvik, Gail P , Hakonarson, Hakon , Gordon, Adam S , Feng, Qiping , Carrell, David , Williams, Marc S , Weng, Chunhua , Pendergrass, Sarah A. , Kullo, Iftikhar J.

Genetic Epidemiology | September 23, 2020 | Volume: 45 | Issue: 1 | Pages: 4-15

10.1002/gepi.22360 Get It

AbstractCarotid artery atherosclerotic disease (CAAD) is a risk factor for stroke. We used a genome‐wide association (GWAS) approach to discover genetic variants associated with CAAD in participants in the electronic Medical Records and Genomics (eMERGE) Network. We identified adult CAAD cases with unilateral or bilateral carotid artery stenosis and controls without evidence of stenosis from electronic health records at eight eMERGE sites. We performed GWAS with a model adjusting for age, sex, study site, and genetic principal components of ancestry. In eMERGE we found 1793 CAAD cases and 17,958 controls. Two loci reached genome‐wide significance, on chr6 in LPA (rs10455872, odds ratio [OR] (95% confidence interval [CI]) = 1.50 (1.30–1.73), p = 2.1 × 10−8) and on chr7, an intergenic single nucleotide variant (SNV; rs6952610, OR (95% CI) = 1.25 (1.16–1.36), p = 4.3 × 10−8). The chr7 association remained significant in the presence of the LPA SNV as a covariate. The LPA SNV was also associated with coronary heart disease (CHD; 4199 cases and 11,679 controls) in this study (OR (95% CI) = 1.27 (1.13–1.43), p = 5 × 10−5) but the chr7 SNV was not (OR (95% CI) = 1.03 (0.97–1.09), p = .37). Both variants replicated in UK Biobank. Elevated lipoprotein(a) concentrations ([Lp(a)]) and LPA variants associated with elevated [Lp(a)] have previously been associated with CAAD and CHD, including rs10455872. With electronic health record phenotypes in eMERGE and UKB, we replicated a previously known association and identified a novel locus associated with CAAD.
Understanding the Return of Genomic Sequencing Results Process: Content Review of Participant Summary Letters in the eMERGE Research Network
Lynch, John , Sharp, Richard R. , Aufox, Sharon , Bland, Harris T. , Zawatsky, Carrie L. Blout , Buchanan, Adam H. , Halverson, Colin , Harr, Margaret , Hebbring, Scott J. , Hoell, Christin , Holm, Ingrid A. , Jarvik, Gail P. , Kullo, Iftikhar, Kochan, David C., Lazzeri, Amanda L., Leppig, Kathleen A. , Madden, Jill A. , Marasà, Maddalena , Myers, Melanie F. , Peterson, Josh F. , Prows, Cynthia A. , Ralston, James D. , Rasouly, Hila Milo , Scrol, Aaron, Smith, Maureen E. , Stuttgen, Kelsey , Wiesner, Georgia L. , Wynn, Julia , Williams, Janet L. , Lynch, John A , Bland, Sarah T , Holm, Ingrid A , Milo Rasouly, Hila , Smith, Maureen E , Williams, Janet L , Myers, Melanie F , Sharp, Richard R , Jarvik, Gail P , Peterson, Josh F , Marasa, Maddalena , Hoell, Christin , Bowen, Deborah J. , Henrikson, Nora B. , Larson, Eric B. , Rahm, Alanna Kulchak , Sturm, Amy C. , Williams, Marc S

Journal of Personalized Medicine | May 14, 2020 | Volume: 10 | Issue: 2 | Pages: 38

10.3390/jpm10020038 Get It

A challenge in returning genomic test results to research participants is how best to communicate complex and clinically nuanced findings to participants in a manner that is scalable to the large numbers of participants enrolled. The purpose of this study was to examine the features of genetic results letters produced at each Electronic Medical Records and Genomics (eMERGE3) Network site to assess their readability and content. Letters were collected from each site, and a qualitative analysis of letter content and a quantitative analysis of readability statistics were performed. Because letters were produced independently at each eMERGE site, significant heterogeneity in readability and content was found. The content of letters varied widely from a baseline of notifying participants that results existed to more detailed information about positive or negative results, as well as materials for sharing with family members. Most letters were significantly above the Centers for Disease Control-suggested reading level for health communication. While continued effort should be applied to make letters easier to understand, the ongoing challenge of explaining complex genomic information, the implications of negative test results, and the uncertainty that comes with some types of test and result makes simplifying letter text challenging.
Returning Results in the Genomic Era: Initial Experiences of the eMERGE Network
Wiesner, Georgia L. , Appelbaum, Paul S. , Aufox, Sharon , Bland, Harris T. , Zawatsky, Carrie L. Blout , Clayton, Ellen Wright , Harr, Margaret , Henrikson, Nora B. , Hoell, Christin , Holm, Ingrid A. , Jarvik, Gail P. , Lammers, Philip E. , Larson, Eric B. , Lindor, Noralane M. , Marasà, Maddalena , Myers, Melanie F. , Peterson, Josh F. , Prows, Cynthia A. , Ralston, James D. , Rasouly, Hila Milo , Sharp, Richard R. , Smith, Maureen E. , Driest, Sara L. Van , Williams, Janet L. , Wynn, Julia , Leppig, Kathleen A. , Appelbaum, Paul , Bland, Sarah T , Clayton, Ellen Wright , Henrikson, Nora , Holm, Ingrid A , Milo Rasouly, Hila , Sharp, Richard R , Smith, Maureen E , Van Driest, Sara L , Williams, Janet L , Myers, Melanie F , Jarvik, Gail P , Peterson, Josh F , Marasa, Maddalena , Hoell, Christin , Rahm, Alanna Kulchak , Christensen, Kurt D. , Chung, Wendy K. , Green, Robert C. , Kullo, Iftikhar J. , Williams, Marc S

Journal of Personalized Medicine | April 28, 2020 | Volume: 10 | Issue: 2 | Pages: 30

10.3390/jpm10020030 Get It

A goal of the 3rd phase of the Electronic Medical Records and Genomics (eMERGE3) Network was to examine the return of results (RoR) of actionable variants in more than 100 genes to consenting participants and their healthcare providers. Each of the 10 eMERGE sites developed plans for three essential elements of the RoR process: Disclosure to the participant, notification of the health care provider, and integration of results into the electronic health record (EHR). Procedures and protocols around these three elements were adapted as appropriate to individual site requirements and limitations. Detailed information about the RoR procedures at each site was obtained through structured telephone interviews and follow-up surveys with the clinical investigator leading or participating in the RoR process at each eMERGE3 institution. Because RoR processes at each of the 10 sites allowed for taking into account differences in population, disease focus and institutional requirements, significant heterogeneity of process was identified, including variability in the order in which patients and clinicians were notified and results were placed in the EHR. This heterogeneity in the process flow for eMERGE3 RoR reflects the “real world” of genomic medicine in which RoR procedures must be shaped by the needs of the patients and institutional environments.