80 years of phenylketonuria. Part IV: Stanislas F. Snieszko and Ada J. Susi and the genesis of the Guthrie test

The aim of this paper was to provide information on remarkable influence of scientists, who emigrated from the East Europe in to the USA, in the entire field of the Guthrie test invention.

While working as graduate assistant at the University of Maine, Robert Guthrie trained in bacteriology with Dr. Stanislas F. Snieszko (1902–1984), “who turned out to be an influential person in his life” (as was stated in Guthrie's biography by JH Koch). Snieszko was born in Krzyz, Poland. He graduated in Jagiellonian University in Krakow. His imprint on fish microbiology was first established as a distinguished professor of bacteriology at Jagiellonian University, and later in the USA as a director of the National Fish Health Research Laboratory at Leetown. Snieszko was a pioneer and a leader in non-parasitological fish diseases and their prevention and control. He had become popular as an outstanding teacher (see well-known Snieszko's diagram of the epidemiological triad presented in 1974) as well as one of the most respected researchers in fishery.

Using the same bacteria and technique applied in bacterial inhibition assays to screen for different antimetabolites in cancer patients, Guthrie and his lab technician, Ada Susi (1918–2002), who was born and educated in Estonia, developed a simple and cheap test for phenylalanine in whole blood dried on filter paper.