Advancing genomics with expertise and leadership
For more than 25 years, our people have brought rigor, collaboration, and purpose to work that improves outcomes for patients.
Our Executive Team
Dr. Davis joined the company in 2011 and currently serves as Chief Laboratory Officer, overseeing clinical laboratory operations across all Tempus laboratories, including Ambry located in Aliso Viejo, CA. The laboratories aim to deliver large-scale intelligent diagnostics with quality data insights to support patient care.
During her tenure, Dr. Davis has held several roles at Ambry, including Chief Operating Officer and Chief Scientific Officer, supporting clinical operations, research and development pipelines, academic collaborations, project management, supply chain, and quality teams. Her commitment to collaborative innovation is evident in her efforts to introduce new technologies into scientific and operational workflows, always striving to find answers for patients. As Laboratory Technical Director, she was involved in clinical reporting operations for cancer, cardiovascular, and general genetics; laboratory testing and validations; diagnostic exome analysis; novel gene discovery; and the AmbryShare exome data-sharing project.
Dr. Davis earned a Ph.D. in Molecular Biology from the University of Southern California as an NIH-NIA Fellow, researching defects in DNA replication and repair related to human disease. She completed post-doctoral training as an NIH Fellow in Clinical Molecular Genetics at the University of California, Los Angeles/Cedars Sinai Medical Center and is certified by the American Board of Medical Genetics and Genomics. Before joining Ambry, Dr. Davis was faculty at Harbor-UCLA Medical Center in the Division of Medical Genetics, where her research focused on developing molecular therapeutics for rare genetic disorders, including lysosomal storage diseases and inherited breast and colon cancer. She is a Clinical Genetic Molecular Biologist Scientist in California and holds a COQ in New York.
Mike Martinson is the Chief Financial Officer of Ambry Genetics Corporation, where he manages the Company’s finances and accounting. Mr. Martinson previously held a role as the Financial Controller at Ambry Genetics. Prior to joining Ambry Genetics, he worked at Squar Milner LLP as a senior auditor with a focus in life sciences. Mr. Martinson received his B.A. in Business Administration-Accounting from California State University Fullerton College of Business and Economics. Outside of work, Mike and his wife Pam enjoy outdoor activities and raising their 2 children.
Tom Schoenherr is responsible for the strategic, financial and operational leadership of the organization.
Tom joined Ambry in 2017 as Chief Commercial Officer and was responsible for the execution of Ambry’s go-to-market strategy and overseeing all commercial functions including service, support, sales, marketing, business development, managed care and genetic specialists. Prior to Ambry, Tom spent more than 20 years in leadership positions in the molecular diagnostics space, most recently as the CCO of Omada Health where he was responsible for driving business growth and increasing market share. He also served in similar roles at Counsyl, Quest Diagnostics, Siemens Healthcare and Abbott Diagnostics. Tom earned his BS from Michigan State University and completed his Executive Business Development Program from the University of Notre Dame.
Michelle Smith is the General Counsel and Corporate Secretary of Ambry Genetics Corporation. Michelle is responsible for overseeing all legal, governance, and compliance matters. Prior to joining Ambry in January 2016, Michelle practiced general corporate law at The Patrón Spirits Company in Las Vegas, Nevada, and intellectual property law at the international law firm of Jones Day in Irvine, California. In law school, she served as an extern for the U.S. Attorney’s Office, Central District in Santa Ana, California. Michelle graduated summa cum laude from the University of California, Los Angeles. She then earned her law degree from the University of Southern California where she served on the Southern California Law Review. She is admitted to practice law in the State of California.
Donavan Cheng is the Chief Science and Technology Officer at Ambry Genetics. He graduated with a PhD in Biomedical Engineering from Johns Hopkins University School of Medicine. In this role, he manages the Informatics and R&D efforts at Ambry. For informatics, he leads a team of bioinformaticians, software development and systems engineers to innovate, architect, and develop pipelines and applications for Ambry’s product portfolio. Donavan leverages his experience in assay development and molecular technologies to advance the company’s R&D efforts. Prior to joining Ambry, Donavan worked at Guardant Health, where he led bioinformatics and assay development efforts for minimal residual disease. At Illumina, he was responsible for product management in Population Genomics/Genetic Health, as well as the BaseSpace Suite of SaaS/PaaS products. Donavan specializes in bioinformatics workflows for identifying targets and biomarkers from high-dimensional molecular profiling data, as well as the analytical validation of NGS-based molecular diagnostics.
Mark Konopka is an experienced sales leader with over a 20 year history of building world-class sales organizations – 15 of those years specifically in the health care space. He is currently the Vice President of Sales with teams covering North America, Western Europe and Latin America. Mark joined Ambry Genetics in January 2018 from Omada Health as their Vice President of Sales. Before that, he held leadership roles for Quest Diagnostics and Counsyl. While at Counsyl, Mark built the sales organization which included over 100 sales reps and sales leaders and grew the company from $1M to over $100M annually in less than 5 years. Mark earned his BS in Mathematics from Ohio University. In his spare time, Mark is involved with coaching youth football and raising money to provide scholarships for high school students going to college.
Dr. Thomas Slavin serves as Chief Medical Officer of Diagnostics, where he brings extensive leadership experience across clinical genetics, molecular diagnostics, and oncology. A physician‑scientist and seasoned biotech executive, Dr. Slavin is recognized for his work advancing genetics‑driven diagnostics and care.
Prior to joining Tempus, Dr. Slavin held senior leadership roles at Quest Diagnostics as Chief Clinical Officer of Molecular Oncology and Medical Director for Haystack MRD. He previously served as Chief Medical Officer at Myriad Genetics. In these roles he has supported the development and clinical integration of innovative diagnostic technologies.
Earlier in his career, Dr. Slavin was an assistant professor at City of Hope National Medical Center, where he remains engaged as faculty in its leading cancer genetics education program. He earned his MD with Alpha Omega Alpha honors from the University of South Florida and completed his pediatrics and genetics residencies at Case Western Reserve University, including a dedicated research year in genetic epidemiology. He also completed advanced clinical research training at USC and holds an MBA from Columbia Southern University.
Dr. Slavin has authored more than 85 peer‑reviewed publications spanning genomic data from over 500,000 patients and has received NIH‑NCI research funding. He contributed to national clinical standards through his work with the NCCN and ClinGen. He serves on the board of Touch4Life.
Dr. Slavin’s work centers on expanding access to high-quality genetic care. By bridging the gap between innovation and clinical application, he focuses on enhancing diagnostic precision and improving long-term patient outcomes.
Catherine Suh leads Human Resources for Ambry Genetics as Senior Vice President, People. She initially joined Ambry in 2016 during a time of hypergrowth for the company to implement a scalable infrastructure that could support a dynamic organization. During her tenure at Ambry, she’s led the company through several transitions including multiple acquisitions and divestitures. Prior to Ambry, Catherine worked at Experian Consumer Services where she gained extensive experience working in a large global organization with heavy M&A activity. For over 15 years, Catherine has worked in highly regulated environments in healthcare, financial technology and biotech. She has worked closely alongside leaders during times of growth and transformation to align the HR strategy with the business strategy. Catherine earned an MBA and a bachelor’s degree in Psychology from the University of California, Irvine.
Our Leadership Team
Joy Rae-Radecki Crandall has a deep commitment to innovation, efficiency, and quality in genetic testing, making her an ideal fit for her role as Vice President of Clinical Laboratory Operations at Ambry Genetics. In this position, Joy drives operational excellence across Ambry’s high-throughput laboratory environment, focusing on advanced automation technologies and clinical accuracy. With over 15 years of experience in laboratory science and clinical diagnostics, Joy’s leadership is defined by her collaborative approach and dedication to advancing precision medicine.
Dr. Chia-Ling Gau is driven by a passion for advancing quality and regulatory excellence, making her an ideal fit for her role as Vice President, Global Head of Quality & Regulatory at Ambry Genetics. In this position, Dr. Gau ensures compliance and quality across Ambry’s operations. She holds a B.A. in Molecular Cell Biology from the University of California, Berkeley, and a Ph.D. in Microbiology, Immunology, and Molecular Genetics from UCLA, where she also completed her postdoctoral fellowship.
Kelly Hagman is driven by a passion for advancing genomic medicine through evidence and strategy, making her an ideal fit for her role as Vice President of Medical Affairs at Ambry Genetics. In this position, , Kelly established the company’s first Medical Affairs department, uniting clinical leaders and driving long-term strategic planning. Kelly oversees teams spanning Clinical Strategy, Clinical Research, Education, and our field-facing Genomic Science Liaisons ensuring clinical strategy enhances innovation and industry engagement. With over 25 years of experience in the clinical laboratory industry and over 50 peer-reviewed publications, Kelly has led transformative initiatives, including launching the industry’s first clinical exome and co-authoring ACMG/AMP guidelines, demonstrating a sustained commitment to advancing genomic medicine.
Dr. Rachid Karam is passionate about bridging cutting-edge technologies to improve patient outcomes, making him an ideal fit for his role as Vice President of Research & Development at Ambry Genetics. In this position, Dr. Karam has spearheaded initiatives to improve the diagnostic yield of DNA tests, including integrating RNA sequencing into clinical genetic testing. He earned his M.D. in Brazil, a Ph.D. in Oncogenetics from the University of Porto, Portugal, and completed a postdoctoral fellowship at the University of California, San Diego.
Greg Nogle is driven by a commitment to advancing reimbursement strategies and payer integration, making him an ideal fit for his role as Vice President of Market Access at Ambry Genetics. In this position, Greg leads efforts to integrate coverage initiatives with CMS/Medicare contractors and drive reimbursement strategies for commercial and government payers. Prior to joining Ambry, Greg held leadership roles in medical device, therapeutics, and diagnostics industries, including positions at Insulet Corporation and Roche Diagnostics. He holds a B.S. from LSU, where he focused on economics and history.
Melissa Parra is driven by a passion for cross-functional execution and innovation, making her an ideal fit for her role as Vice President of Operations, PMO & Continuous Improvement at Ambry Genetics. In this position, Melissa leads the Continuous Improvement Office and Scaled Agile Delivery Group, transforming how Ambry delivers innovation. Since joining Ambry in 2010, she has led cross-functional teams through major milestones, including overseeing many of Ambry’s major product launches such as the launching the first NextGen sequencing platform, the first Clinical exome product on the market, the first Cancer NGS platforms on the market, and the RNAInsight launches. She was integral in establishing much of the functionality and system infrastructure within Ambry, including the foundational design of Ambry’s variant analysis software AVA. Melissa holds a BS in Molecular Genetics from UC Davis and an MS in Genetic Counseling from California State University, Northridge.
Tina Pesaran is a seasoned genomic science leader with over 20 years of experience in clinical genetics, variant interpretation, and strategic program development. As Vice President of Genomic Science at Ambry Genetics, she oversees a multidisciplinary team driving advancements in variant and gene assessment, medical informatics, and computational biology. Tina has been instrumental in shaping Ambry’s classification frameworks, scaling operations, and guiding industry standards through cross-functional leadership and evidence-based genomics.
Brittany Rambino, CPC-P, is driven by a passion for financial accuracy and operational excellence, making her an ideal fit for her role as Vice President of Revenue Cycle Management at Ambry Genetics. In this position, Brittany oversees patient financial services, drives revenue integrity, and leads strategic initiatives to optimize reimbursement. Prior to joining Ambry, she founded Precision Medical Revenue Solutions, providing RCM consulting and implementation services, and played a key role in securing new reimbursement pathways for emerging healthcare innovations. Brittany is a Certified Professional Coder – Payer (CPC-P) with expertise spanning laboratory, molecular diagnostics, and specialty pharmacy revenue operations.
AJ Stuenkel is a genetic counselor by training with a passion for leveraging technology to improve result quality and talent use. In his role as Vice President of Clinical Diagnostics at Ambry Genetics, AJ oversees post-analytical functions within clinical operations, including result analysis, interpretation, and reporting. Since joining Ambry in 2011, AJ has focused on operational scalability, health monitoring, and capacity planning to support rapid growth and scientific excellence. He holds a Master’s degree from Boston University School of Medicine and a B.S. in Genetics from the University of California, Davis.
Careers at Ambry
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