Head of French laboratories specialized in biomedical sciences between years 1984 and 2007, he was elected President of the Paris Descartes University in December 2007, as the sole candidate.

"[3] In 2004, Kahn signed a petition and threatened to resign from his post as head of the Paris-based, publicly financed Cochin Institute, due to cuts in government spending on research.

[citation needed] In 1995, Kahn was a notable opponent of intracytoplasmic sperm injection, which he saw as an experimental treatment not to be used by those with infertility, which was not serious enough to justify the risks he perceived the procedure as having.

In speaking out against the case of a 62-year-old Frenchwoman who gave birth after being implanted in the United States with the sperm of her brother, Kahn protested what he called "social incest" and continued, "The most important thing is that doctors were involved in this process, and they did it because they were paid handsomely.

[3] Kahn has said that there can be no lasting state of Israel in its current location - "Demography, law and the uneasy conscience of the West preclude it.