 He also served as Professor in the Graduate Program of the Department of Genetics at George Washington University and formerly as Adjunct Professor in the Department of Chemical and Biochemical Engineering at the University of Maryland.He served on the editorial boards of several scientific journals, and was a member of the Scientific Steering Committee for Blood Products at Walter Reed Army Institute of Research and Chairman for the Panel on Biotechnology of the National Research Council.Drohan died of lung cancer at his home in Germantown, Maryland after a four-year illness.