[6][7] Kaelin earned his bachelor's degree in mathematics and chemistry at Duke University, and stayed to attain an MD, graduating in 1982.

[9] He serves as vice-chair of Scientific Programs on the Damon Runyon Cancer Research Foundation Board of Directors and Chair of the Damon Runyon Physician-Scientist Training Award selection committee and is a member of the board of directors at Eli Lilly[8] and the Stand Up to Cancer scientific advisory committee.

[11] Kaelin's research found that in VHL subjects, there are genes that express the formation of a protein critical in the EPO process, but which the mutation suppressed.

Kaelin's work aligned with that of Peter J. Ratcliffe and Gregg Semenza who separately had identified a two-part protein, hypoxia-inducible factors (HIF) that was essential to EPO production and which was triggered by oxygen levels in the blood.

[12] The combined work of Kaelin, Ratcliffe, and Semenza identified the pathway of how cells detect and react to oxygen levels in the blood, and have led to the development of drugs to help patients with anaemia and kidney failure.