The Tuskegee Syphilis Study was a notorious unethical medical experiment conducted by the U.S. Public Health Service from 1932 to 1972. The study was carried out in Tuskegee, Alabama, and involved 600 African American men, 399 of whom had syphilis and 201 who did not.

The purpose of the study was to observe the natural progression of untreated syphilis in African American men. The participants were not informed about the true nature of the study, and they were not provided with proper medical treatment for their condition, even after penicillin became widely available as a cure for syphilis.

The study continued for 40 years, despite the unethical treatment of the participants and the fact that it violated basic ethical standards of medical research. It wasn't until 1972, when the study was exposed by the media, that it was finally brought to an end.

The Tuskegee Syphilis Study highlighted the systemic racism and exploitation of African Americans in medical research and led to significant changes in research ethics and regulations to protect the rights and well-being of study participants.