Alfred George Knudson, Jr. (August 9, 1922 – July 10, 2016) was an American physician and geneticist specializing in cancer genetics.

Among his many contributions to the field was the formulation of the Knudson hypothesis in 1971,[1] which explains the effects of mutation on carcinogenesis (the development of cancer).

[3] After an initial faculty appointment at the City of Hope Medical Center in California, Knudson became the Associate Dean for Basic Sciences at the State University of New York at the Stony Brook School of Medicine.

"[7] He received numerous prizes and honorary doctorates for his work, most prominently the 1998 Albert Lasker Award for Clinical Medical Research.

[13][3] His wife of 40 years, Anna Meadows, was a distinguished pediatric oncologist (now retired) at the Children's Hospital of Philadelphia at the University of Pennsylvania.