Thyrotropin in San Diego: Echoes After Nearly a Century

Dear Editor:

I noticed that the upcoming annual American Thyroid Association (ATA) meeting in San Diego occurs nearly a century after the first high-quality scientific presentations about a putative pituitary thyrotropic factor were given at the meeting of the Western Society of Naturalists in San Diego in August 1916. Bennet Allen of the University of Kansas and Philip Smith who was then at the University of California, Berkeley, had independently studied how removal of the pituitary from young tadpoles caused diminished thyroid colloid, and they gave separate oral presentations. The tadpoles failed to proceed through metamorphosis due to a lack of thyroid hormone, and they took on an impressive silvery color that we today know was due to absence of melanocyte-stimulating hormone. The California connection with the story of thyrotropin (TSH) only starts there, since Allen later moved to the University of California, Los Angeles, where he had a long and distinguished career. Decades later, John Pierce et al. at the University of California, Los Angeles, made vital biochemical discoveries about the structure of TSH. Interested readers can learn more about these early days of discoveries about TSH in a recent historical note published in the European Thyroid Journal. ¹