Nathans was born in 1928 in Delaware. He was the last of nine children born to Samuel and Sarah Nathans, Russian Jewish immigrants. Nathans received his B.A. from the University of Delaware in 1950 and his M.D. from Washington University in St. Louis in 1954. It was during the summer after his first year of medical school that Nathans had his initial exposure to laboratory work.

After medical school, Nathans completed a one-year internship at Columbia-Presbyterian Medical Center. After this, he spent two years (1955-57) at the National Cancer Institute as a clinical associate studying protein synthesis. In 1956, Nathans married Joanne Gomberg, with whom he had three sons. Returning to Columbia-Presbyterian, Nathans completed his residency in 1959. That same year Nathans won a United States Public Health Service grant to do biochemical research at Rockefeller University in New York with Fritz Lipmann and Norton Zinder. It was at this point...