Fearon was born to parents Margaret and Ross in Maine and grew up alongside his older sister Gretchen.
During his graduate studies at Johns Hopkins, Fearon was inducted into the Phi Beta Kappa.
[3] After receiving his medical and doctoral degrees, Fearon conducted his postdoctoral research in the laboratory of Chi Van Dang, where he developed a system for the study of protein-protein interactions in living mammalian cells.
[6] In 1999, Fearon was elected a Fellow of the American Society for Clinical Investigation (ASCI).
"[10] In 2018, Fearon was named a fellow of the American Association for the Advancement of Science for "distinguished contributions to the cancer field, particularly in defining the role of accumulated mutations in oncogenes and tumor suppressor genes in colon cancer pathogenesis.