Born Karl- Heinz Tanzyna, he was adopted by the Jena family Hahnemann shortly after his birth. He never met his biological mother. From 1965 to 1970 he studied architecture in Weimar and began using the name Gino. Having finished his studies, he began working for Hermann Henselmann, one of the best-known GDR architects.
While still working as an architect he received an offer to work as a model. Soon he quit his office job and became one of the few state-approved menswear models in the GDR. He also worked as a costume- and stage designer in theatres in Berlin, Brandenburg and Mecklenburg-Western Pomerania. He was the last stage designer at the Palast der Republik in Berlin.
He was open concerning his belonging to the LGBT communities, wrote poetry and prose and is considered to be one of the first GDR writers who openly dealt with homosexuality in his works. He saw himself as part of the artistic “Underground”. In the 80s his poetry and prose appeared in underground magazines like „Schaden“, “Entwerter/Oder”, “U.S.W.”, der „Ariadnefabrik“ and many more.
During the same time he experimented with and sought to test the boundaries of Super-8 filming. He filmed his own scripts as an independent director. According to the historian Claus Löser, without Hahnemann’s contributions, the independent film scene in the GDR would have developed much differently. As film-maker, he was also part of the “Underground” and showed his own, independent view of the GDR-reality with his movies.
He showed his work at single- and group exhibitions organized multimedia performances and readings. He published self-made artist’s books, developed set scenery and remained a writer and cultural figure even after the fall of the wall. In 1993 he initiated as an author, programme director and presenter the yearly “Bildsalon” at the Literaturforum im Brecht-House Berlin. He translated works by the American poet John Eppstein into German, took part in exhibitions like "BERLIN-MOSKAU 1950-2000” and also contributed works to the “3. Biennale for contemporary art” 2004 in Berlin.
He received a number of scholarships: from the Berlin Senate, Academy Castle Solitude Stuttgart and the Villa Massimo in Rome, as well as the Alfred-Döblin-scholarship of the Berlin Academy of Arts.
