Jonathan Klein

Jonathan Klein, MD

Medical Director

Shelton, Connecticut

T (203) 926-7158


Dr. Klein is board certified in anatomic and clinical pathology, hematopathology and molecular genetic pathology.  He earned his medical degree from Sackler School of Medicine, New York State program, Tel Aviv, Israel. He completed his residency in anatomic and clinical pathology at Winthrop University Hospital, Mineola NY, where he served as chief resident and performed his fellowship training in hematopathology and molecular genetic pathology at Washington University – Barnes Jewish Hospital, St. Louis, MO.  Dr. Klein previously served as laboratory director and chief medical officer of Molecular Pathology Laboratory Network in Maryville, TN.  His special interests include neoplastic hematopathology, molecular diagnostics and FISH in oncology, and clinical trial laboratory testing. In addition to his role at Dianon Pathology, Dr. Klein serves as medical director of Integrated Oncology. He is a member of American Society for Clinical Pathology and Association for Molecular Pathology.

James B. Amberson, MD

Vice President of Pathology, Dianon Pathology

Shelton, Connecticut

T (203) 926-7158


Dr Amberson is board certified in anatomic pathology and cytopathology. He received his medical degree from The Johns Hopkins University School of Medicine and completed residency training in pathology at the New York Hospital-Cornell University Medical Center. He was a cytopathology fellow under Leopold Koss, MD, at Montefiore Medical Center, Bronx, NY. He also holds an MBA from Columbia University. Dr Amberson was an assistant professor of pathology at the Cornell University School of Medicine from 1983 to 1989, after which time he became Dianon’s medical director. His area of expertise is uropathology, and he has authored articles about general pathology, urology, flow cytometry, and image cytometry that have been published in various medical and scientific journals.