Roger Charles Louis Guillemin (French pronunciation: [ʁɔʒe ʃaʁl lwi ɡijmɛ̃]; January 11, 1924 – February 21, 2024) was a French-American neuroscientist.

Their partnership dissolved after five years due to lack of progress and personal conflicts; Schally moved to the Veterans Affairs Hospital in New Orleans.

In 1969, as government funding was about to be cut off, Roger Burgus from Guillemin's team made a breakthrough, identifying the thyrotropin-releasing factor (TRF), which controls the thyroid gland.

This achievement secured continued funding and led to the identification of another releasing factor, FRF, which controls reproductive systems.

[2] Guillemin signed along with other Nobel Prize winners a petition requesting a delegation of the Committee on the Rights of the Children of the United Nations to visit a Tibetan child who had been under house arrest in China since 1995, namely Gedhun Choekyi Nyima, recognized as the 11th Panchen Lama by the 14th Dalai Lama, Tenzin Gyatso.