Abstract
Viruses recovered after transfection of chicken cells with DNA isolated from virogenic mammalian cells were characterized by serum neutralization, virus interference and host range tests. The virus obtained after transfection with DNA from XC cells containing the genome of the PRAGUE strain of Rous sarcoma virus (PR-RSV) had the properties of subgroup C avian sarcoma viruses. The virus isolated after transfection with DNA from RSCH cells containing the genome of the SCHMIDT-RUPPIN strain of Rous sarcoma virus (SR-RSV) exhibited the properties of subgroup D viruses. The subgroup classification of described viruses corresponds with classes of virus genomes present in virogenic cells.