Medical and Scientific Staff

Kelly Y. Chun, PhD

Vice President, Labcorp; Scientific Director, Endocrine Sciences

Dr Chun received her PhD in biochemistry from the Medical College of Wisconsin and trained as a postdoctoral fellow in laboratory medicine at Harvard Medical School. She has more than 20 years of experience in protein science and assay development and validation. She joined Esoterix in 2002 as a technical director. She oversees chemistry tests, endocrine immunoassays, and immunogenicity testing.

Over the years, Dr Chun has developed and validated a number of pivotal endocrine and autoimmune assays for pharmaceutical trial and clinical diagnostic use. She lectures on a national level and has authored articles and book chapters with a focus on endocrinology and immunogenicity. She is a member of the Endocrine Society, American Diabetes Association, and the American Association of Clinical Chemistry.

Samuel H. Pepkowitz, MD

Medical Director, Endocrine Sciences

Dr Pepkowitz is board certified in pediatrics, anatomic pathology, and clinical pathology and has a special qualification in blood banking. He received his medical degree from the Columbia University College of Physicians and Surgeons. Dr Pepkowitz is a member of the American Academy of Pediatrics, the American Society of Clinical Pathologists, the College of American Pathologists, the American Medical Association, the American Association of Blood Banks, Pediatric Endocrine Society and the Society for Pediatric Pathology.

Toni R. Prezant, PhD

Director of Molecular Genetics, Endocrine Sciences

Dr Prezant is board certified in clinical molecular genetics by the American Board of Medical Genetics and Genomics and is licensed in California and certified in New York State as a laboratory director. She earned her PhD in biology from the Massachusetts Institute of Technology. Dr Prezant has more than 12 years of clinical experience in molecular genetic testing and an extensive research background, including studies of mitochondrial DNA diseases and pituitary tumorigenesis. Dr Prezant develops and validates new tests for Endocrine Sciences’ molecular genetics laboratory. She is a member of the American Society of Human Genetics and the Association for Molecular Pathology.

Brett Holmquist, PhD

Associate Scientific Director

Dr Holmquist is board certified by the American Board of Clinical Chemistry, a fellow of the National Academy of Clinical Biochemistry, licensed by the state of California as a clinical chemist, and certified as a New York State laboratory director. He earned his PhD in biochemistry and molecular biology from the University of California, Riverside.  He has worked for more than 25 years in the life science industry, including more than 12 years in the diagnostic laboratory industry. He is a member of the Endocrine Society, the American Society for Mass Spectrometry, the American Society for Clinical Pathology, the American Society for Clinical Laboratory Science, and the American Association of Clinical Chemistry.