The human gene encodes a protein containing one KRAB domain and fifteen zf-C2H2 domains. Domain order of rhesus homologous gene resembles human gene, we proposed they represent the ancestral state. Chimpanzee homologous gene and orangutan homologous gene have experienced their specific deletion. Gibbon homologous gene experienced its specific domain deletion due to a PTC. The orangutan homologous gene of human ZNF816 is manually predicted.