Leadership Team

jason ryan

Executive Chair of the Board

jason ryan

Executive Chair of the Board

Jason Ryan is Executive Chair of GeneDx’s Board of Directors. Jason held this same role at Sema4 prior to the company being renamed to GeneDx in January 2023. Jason began serving on Sema4’s Board of Directors in July 2021 and assumed the role of Executive Chair six months later.

Jason has held numerous executive leadership and board roles in diagnostics and therapeutics companies, with broad experience in scaling businesses from early stage through product launch and commercialization.

Jason most recently served as COO and CFO of Magenta Therapeutics (Nasdaq: MGTA), a company focused on developing novel medicines for patients with autoimmune diseases and blood cancers. Prior to that, Jason was CFO of Foundation Medicine, a transformative company in oncology molecular profiling. He helped lead that business through early development, its initial public offering, subsequent growth into a global commercial organization and ultimately, its acquisition by Roche Holdings (Nasdaq: RHHBY). Before Foundation Medicine, Jason led the finance and strategic planning efforts of several other high growth life science companies.

In addition to GeneDx, Jason currently serves on the board of directors of Singular Genomics (Nasdaq: OMIC) and previously served on the board of directors of ArcherDX, Inc. (acquired by Invitae Corporation (NYSE: NVTA)).

He began his career at Deloitte & Touche, where he earned a CPA, and he received a BA in Economics from Bates College and an MBA from Babson College.

eli casdin

Board Member

eli casdin

Board Member

Eli Casdin has served on the Board of Directors at GeneDx (formerly Sema4) since July 2021.

Eli founded Casdin Capital in 2011 and serves as Chief Investment Officer and Founder. Casdin Capital engages as productive investor-partners, helping to fuel the visions of industry leaders by adding expertise and experience to their funding. Focused on emergent technologies in life sciences for more than two decades, Eli has been active in both private and public capital markets, following a passion for analyzing and investing in new technologies and business models within the life sciences and healthcare industry.

Prior to Casdin Capital, Eli served as Vice President at Alliance Bernstein’s thematic investment arm, focusing personally on new technologies for the life sciences and healthcare sectors. While there, he authored the 2011 black book, “The Dawn of Molecular Medicine,” detailing the (then) early-yet-accelerating wave of innovations transforming healthcare and creating opportunity for investors from testing to targeted medicine, and diagnostics to industrial agriculture.

Earlier, Eli worked as a financial analyst at Bear Stearns and Cooper Hill Partners, a healthcare-focused investment firm.

In addition to Sema4, Eli currently serves as a director or an observer on various boards for a number of public and private life sciences companies, trade groups and academic institutes including Rockefeller University, the New York Genome Center Board, and The Columbia University School of General Studies Board of Visitors.

Eli earned a BS from Columbia University and an MBA from Columbia Business School.

dennis charney

Board Member

dennis charney

Board Member

Dennis Charney, MD, has served on the Board of Directors at GeneDx (formerly Sema4) since June 2017.

Dr. Charney is also currently Anne and Joel Ehrenkranz Dean of the Icahn School of Medicine at Mount Sinai and President for Academic Affairs for the Mount Sinai Health System. He is a world expert in the neurobiology and treatment of mood and anxiety disorders, making fundamental contributions to the understanding of the causes of human anxiety, fear, depression, and resilience, and the discovery of new treatments for mood and anxiety disorders.

Dr. Charney was recruited to Icahn School of Medicine at Mount Sinai in 2004 as Dean of Research. In 2007, he became the Dean of the School and Executive Vice President for Academic Affairs of the Medical Center. In 2013, he was also named President for Academic Affairs for the Health System.

Under Dr. Charney’s leadership, the Icahn School of Medicine has risen to a rank of 13th among U.S. medical schools in National Institutes of Health (NIH) funding. As the sole medical school partnering with the seven hospitals of the Mount Sinai Health System, the School has one of the most expansive training and research footprints in the nation. Early in his tenure as Dean, Dr. Charney unveiled Mount Sinai’s $2.25 billion strategic plan that laid the foundation for the 17 robust Research Institutes that Mount Sinai is known for today. In 2017, Dr. Charney launched a five-year strategic plan for the School focusing on research and education. This new strategic plan provides a roadmap for continued interdisciplinary collaboration, innovation and discovery, with special emphasis on growth in precision medicine, immunotherapy, neurosciences, cancer, and cardiology.

In the Health System, Dr. Charney is currently developing the structure for complementary Clinical Institutes that will serve as Centers of Excellence for cancer, heart disease, diabetes, HIV, pulmonary diseases, and more, with the anticipation that this architecture — compatible research and clinical institutes — will further eliminate silos and generate game-changing models in clinical excellence and standards of care.

Dr. Charney’s career began in 1981 at Yale, where, within nine years, he rose from Assistant Professor to Professor of Psychiatry with tenure, a position he held for a decade. At Yale, he chaired the NIMH Board of Scientific Counselors, which advises the Institute’s director on intramural research programs. In 2000, NIMH recruited Dr. Charney to lead its Mood and Anxiety Disorder Research Program — one of the largest programs of its kind in the world —and the Experimental Therapeutics and Pathophysiology Branch.

Dr. Charney’s own research on depression has led to new hypotheses regarding the mechanisms of antidepressant drugs and discovery of new and novel therapies for treatment resistant depression including Lithium and Ketamine. The work demonstrating that Ketamine is a rapidly acting antidepressant has been hailed as one of the most exciting developments in antidepressant therapy in more than half a century. More recently, his pioneering research has expanded to include the psychobiological mechanisms of human resilience to stress.

Elected to the Institute of Medicine of the National Academy of Sciences in 2000, Dr. Charney has been honored with every major award in his field for his scientific research. He is also a prolific author who has written or co-authored more than 700 publications, including groundbreaking scientific papers, chapters, and books. His studies on human resilience, which identified ten key resilience factors for building the strength to weather and bounce back from stress and trauma, are summarized in an inspiring book, “Resilience: The Science of Mastering Life’s Greatest Challenges” co-authored by Steven Southwick.

emily leproust

Board Member

emily leproust

Board Member

Emily Leproust, PhD, has served on the Board of Directors at GeneDx (formerly Sema4) since July 2021.

Emily is currently the CEO and Co-Founder of Twist Bioscience (Nasdaq: TWST), which manufactures synthetic DNA and DNA products for customers in a wide range of industries. Emily is recognized as an early pioneer in the high-throughput synthesis and sequencing of DNA. Her work is disrupting markets to enable the exponential growth of DNA-based applications including chemicals/materials, diagnostics, therapeutics, food and digital data storage.

In 2020, BIO presented Emily with the Rosalind Franklin Award for Leadership. She was also named by Foreign Policy as one of their 100 Leading Global Thinkers and by Fast Company as one of the Most Creative People in Business.

Prior to Twist Bioscience, Emily held escalating positions at Agilent Technologies, where she architected the successful SureSelect product line that lowered the cost of sequencing and elucidated mechanisms responsible for dozens of Mendelian diseases. Emily also developed the Oligo Library Synthesis technology, where she initiated and led product and business development activities for the team. She designed and developed multiple commercial synthesis platforms to streamline microarray manufacturing and fabrication.

In addition to GeneDx, Emily currently serves on the Board of Directors of CM Life Sciences and is a co-founder of Petri, an accelerator for start-ups at the forefront of engineering and biology. She has published over 30 peer-reviewed papers – many on applications of synthetic DNA, and is the author of numerous patents.

Emily earned her PhD in Organic Chemistry from University of Houston and her M.Sc. in Industrial Chemistry from the Lyon School of Industrial Chemistry.

keith meister

Board Member

keith meister

Board Member

Keith Meister has served on has served on the Board of Directors at GeneDx (formerly Sema4) s since January 2022.

Currently, Keith is also Managing Partner and Chief Investment Officer of Corvex Management LP, which he founded in December 2010.

Prior to founding Corvex, Keith served as Chief Executive Officer and then Principal Executive Officer and Vice Chairman of the Board of Icahn Enterprises from August 2003 to August 2010. From its launch in November 2004 to August 2010, he also served as Senior Managing Director of the General Partners of Icahn Partners LP and affiliated funds. Prior to joining the Icahn Organization, Keith served as Co‐President of J Net Ventures from January 2000 through September 2001. Prior to launching J Net Ventures, he worked at NorthStar Capital and Lazard Freres.

In addition to GeneDx, Keith currently serves on the Board of Directors for MGM Resorts and BetMGM. He has previously served as a director on numerous other public boards including Yum! Brands, Inc., The Williams Companies, The ADT Corporation, Ralcorp Holdings, and Motorola/Motorola Mobility, among others. He is also Chairman of the Board of Directors for Harlem Children’s Zone and a member of the Board of Trustees for the American Museum of Natural History.

Keith received an A.B. in government, cum laude, from Harvard College in 1995.

mike pellini

Board Member

mike pellini

Board Member

Mike Pellini, MD, has served on has served on the Board of Directors at GeneDx (formerly Sema4) since August 2019.

Currently, Mike is also a Managing Partner of Section 32, a venture capital fund investing at the frontiers of technology, healthcare and life sciences. Previously, he served as CEO and Chairman of Foundation Medicine (NASDAQ:FMI), a company that transformed the way pharmaceutical companies and physicians evaluate the genomic changes underlying a patient’s cancer, until he transitioned to chairman through the close of Roche’s (NASDAQ:RHHBY) acquisition of FMI in August 2018. Before that, he was President and COO of Clarient (NASDAQ:CLRT), a national leader in molecular pathology, which was acquired by GE Healthcare in 2010.

In addition to GeneDx, Mike currently serves as a member of the Board of Directors for Tango Therapeutics, Nusano, Vineti, Singular Genomics, Adaptive Biotechnologies, Octave Health, Thrive Earlier Detection, Cradle Genomics, the Personalized Medicine Coalition, the GO2 Foundation, and the Mission Hospital Foundation (Providence/St. Joseph Health). Mike brings a breadth of understanding in personalized medicine, with a particular interest in and focus on defeating cancer. He is also a member of the President’s Leadership Council at Thomas Jefferson University and Jefferson Health, as well as the Advisory Board for Mission Hospital’s Cancer Institute (Providence/St. Joseph Health).

Mike earned his MD from Jefferson Medical College, his MBA from Drexel University, and his B.A. from Boston College.

richard pfenninger, jr.

Board Member

richard pfenninger, jr.

Board Member

Richard Pfenniger, Jr. has served on has served on the Board of Directors at GeneDx (formerly Sema4) since May 2022.

Richard is an experienced executive with significant expertise in the life science, healthcare, and education fields.

During his career, Richard has been an executive officer at several companies, including CEO and President of Continucare Corporation, a provider of primary care physician and practice management services, where he also served as Chairman of the Board of Directors. Previously, he was the CEO and Vice Chairman of Whitman Education Group, Inc. Prior to joining Whitman, he served in several different roles at IVAX Corporation, including COO, Senior Vice President- Legal Affairs, and General Counsel. Before that, Richard was engaged in the private practice of law.

In addition to GeneDx, Richard currently serves as a member of the Board of Directors for Opko, Inc. (NASDAQ: OPK), a multinational biopharmaceutical and diagnostics company, Asensus Surgical, Inc. (NYSE: ASXC), a medical device company, and Cocrystal Pharmaceuticals, Inc. (NASDAQ: COCP), a clinical stage biotechnology company. He is also the Vice Chairman of the Board of Trustees and a member of the Executive Committee of the Phillip and Patricia Frost Museum of Science.

Richard previously served as a director of GP Strategies Corporation (NYSE: GPX), a corporate education and training company, BioCardia, Inc. (NASDAQ: BCDA), a clinical-stage regenerative medicine company developing novel therapeutics for cardiovascular diseases, and Wright Investors’ Services Holdings, Inc. (OTC US: IWSH), an investment management and financial advisory firm.

Richard received a Juris Doctor degree from the University of Florida and a Bachelor of Business Administration degree from Florida Atlantic University.

joshua ruch

Board Member

joshua ruch

Board Member

Joshua Ruch has served on has served on the Board of Directors at GeneDx (formerly Sema4) since November 2017.

Currently, Joshua is also co-founder and CEO of Rho Capital Partners, an investment and venture capital management company based in New York and Palo Alto. Rho’s activities include investing in information technology, communications, new media, health care, and energy technology, as well as investing in private equity funds and public securities. Before co-founding Rho in 1981, Joshua worked as an investment banker at Salomon Brothers in New York.

In addition to GeneDx, Joshua currently serves as a member of the Board of Directors for Enerkem, Fractal Systems, CloudPay, Code Ocean, and Laer.ai. He is also a trustee of the Mount Sinai Health System, Carnegie Hall and the National Humanities Center, and is a member of the Board of Governors of the Technion – Israel Institute of Technology.

Joshua received an MBA from the Harvard Business School and a BSc in electrical engineering from The Technion in Haifa, Israel. He was born in Belgium and grew up in South Africa. Joshua met his wife, Julia, at The Technion and they have three sons and five grandchildren.

rachel sherman

Board Member

rachel sherman

Board Member

Rachel Sherman, MD, MPH, FACP®, has served on has served on the Board of Directors at GeneDx (formerly Sema4) since March 2020.

Currently, Rachel is also President of Rachel Sherman Partners LLC. She is assisting national and international clients in medical product development and regulation. Rachel is applying her expert knowledge of regulatory science and extensive experience in medical product evaluation and approval to address regulatory challenges at all stages of product development.

Rachel is an accomplished executive and is well known for her innovative, patient-centered approaches to solving complex policy questions. She served until January 2019 as Principal Deputy Commissioner at the U.S. Food and Drug Administration (FDA), where she spent the last 30 years in medical product development and regulation, honing her proficiency at managing the complex dynamics of small- and large-scale organizations in both public and private sectors.

Rachel’s medical and regulatory experience spans a broad range of subject matters, including biosimilars, expedited drug development, infectious diseases, good clinical practice, prescription drug promotion, and active postmarket surveillance. She fostered multiple FDA efforts to modernize and expedite traditional drug development programs, enabling the FDA to respond to public health needs in a nimble, patient-centric, and scientifically rigorous manner. The FDA’s entire process for licensing biosimilar biological products, an extensive effort following statutory changes in 2010, was designed, developed, and implemented under her leadership.

In addition to GeneDx, Rachel currently serves as a member of the Board of Directors for Aptinyx and is a part-time lecturer at the Department of Population Health, Harvard Pilgrim Health Care Institute.

Among Rachel’s many FDA awards are the FDA Distinguished Career Service Award, the Commissioner’s Special Citation (2006 and 2008), the FDA Award of Merit, and multiple Center for Drug Evaluation and Research (CDER) Center Director’s Special Citations. Rachel earned her MD at Mount Sinai School of Medicine and her MPH at Johns Hopkins University. She is the author or co-author of approximately 30 articles in peer-reviewed journals.

katherine stueland

Board Member and CEO

katherine stueland

Board Member and CEO

Katherine Stueland is CEO of GeneDx and has served on the Board of Directors at GeneDx (formerly Sema4) since May 2022. Katherine leads the GeneDx team in its mission to unlock insights from data, leading to healthier lives and a healthier society. She was appointed CEO of GeneDx in 2021 and also served as CEO of Sema4 after the two companies combined in 2022.

Katherine has more than 25 years of experience in the healthcare sector, overseeing multiple commercial organizations from start-up to scale-up and leading corporate brand transformations. Katherine’s career has been driven by her passion for how genomics can improve health outcomes and the importance of broadening research to diverse patient populations to advance science and patient care for all.

Prior to leading GeneDx, Katherine was the Chief Commercial Officer of Invitae Corporation, where she established the corporate brand as the company evolved from a private to a public entity with a market capitalization exceeding $6 billion. Before that, she served as Vice President of Communications and Investor Relations at Dendreon, the first company to bring an immuno-oncology product to market.

Katherine holds a Bachelor of Science in English Language and Literature from Miami University in Ohio.