He received his B.Sc at the University of Toronto, then his M.Sc. in the Department of Biochemistry under the supervision of Dr. Margaret Rand. He obtained his M.D. from the University of Toronto in 1994, then did Core Internal Medicine training at the same institution. Dr. Gross then did clinical training in Hematology and Oncology at Beth Israel Deaconess Medical Center, a Harvard Medical School teaching hospital, in Boston, MA. Dr. Gross then spent four years as a postdoctoral fellow in the laboratory of Drs. Bruce and Barbara C. Furie at the Center for Hemostasis and Thrombosis Research at Harvard Medical School.