Dennis John Ashbaugh (born 1946 in Red Oak, Iowa) is an American painter and artist who lives and works in New York City.
He was the first performer to employ DNA marking patterns in paintings, in his 1992 show Designer Gene. Ashbaugh’s use of well-ventilated and color in his large scale paintings of autoradiographs have drawn comparison to Mark Rothko.
He is the longtime companion of author Alexandra Penney and grandfather of Celeste Penney. He has been characterized by the New York Times as a “charismatic ex‐surfer whose residence book can probably retain its own adjoining that of the most severe jet set type”.