Abstract
A defective interfering genome of the parvovirus H-1, called dl1, has been isolated and characterized. The only alteration in dl1 that has been detected is a 300-base-pair deletion at map position 38. Replicative form DNA replication of dl1 requires the RF rep function of a helper virus and the parvoviruses H-1, H-3, MVM, or MVM(i), but not LuIII complement dl1 for replicative form DNA replication.