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. He is a member of American Society for Clinical Pathology and Association for Molecular Pathology.