SUMMARYDNA ofhuman spumaretrovirus (HSRV) was cloned from both cDNA and from viral DNA into phage A. and bacterial plasmid vectors. The recombinant plasm.ids harboring viral DNA were characterized by Southem blot hybridization and restriction mapping. Physical maps were constructed from cDNA and found to be colinear with the restriction maps obtained from viral DNA. The recombinant clones isolated contained viral DNA inserts which rangein size from 2.2 kb to 15.4 kb. The recombinant clones allowed to construct a physical map of the complete HSRV provirus of 12.2 kb.