DR. JOHN WYNIA WINKERT, 56, a retired medical researcher with the Armed Forces Institute of Pathology and a former teacher at Bowie State College, was killed July 22 in a single-automobile accident near Manning, S.C.

A spokesman for the South Carolina Highway Patrol said Dr. Winkert's car ran off Rte. I-95 and crashed into a tree.

Dr. Winkert was born in Brooklyn, N.Y., and graduated from the Brooklyn Polytechnic Institute. He earned his doctorate in physiology from New York University in 1960.

From 1961 to 1964, he taught at the New York Medical College. For the next three years, he was a professor at the State University of New York in Buffalo. He taught at Meharry Medical College in Nashville from 1967 to 1972. While there, he conducted research that led to the discovery of erythropoietin, a hormone that stimulates the development of red blood cells.

Dr. Winkert moved to the Washington area in 1972 and joined the staff at the Armed Forces Institute. During the same period, he taught at Bowie State College. He retired in 1978.

He was a member of the D.C. Roadrunners, the Howard County Strikers, the Prince George's Running Club, and the Potomac Valley Seniors.

Survivors include his wife Elizabeth, of Bowie; four sons, John, of College Park, George, of Laurel, Thomas, of Greenbelt, and Daniel, of Bowie; his mother, Mabel Winkert of St. Petersburg, Fla., and one brother, Theodore, of Manlius, N.Y.