The scientific work of Propping spans genetically complex diseases, especially affecting brain function such as alcoholism, manic depressive disorders, schizophrenia, epilepsy, and in addition hereditary cancer predispositions.
Propping studied medicine at the Free University of Berlin from 1962 to 1968, receiving his MD degree in 1970 based on experimental work in pharmacology.
After having received his license to practise medicine, he became a research assistant at the Institute of Anthropology and Human Genetics of the University of Heidelberg.
Propping showed that the intra-animal culture of bacteria (host-mediated assay) designed to induce mutations by chemical agents reflects the metabolism of the host.
[8] In Bonn, Propping initiated a long-term study in order to analyse the genetic contribution to manic depression.
[15][16][17] Propping received the following awards for his merits in medical genetics : In 1997 he was a member of the Advisory Board of the German Cancer Aid and became chairman in 2003.