Abnormal 3' junctions of the HIV-1 provirus in DSB repair enzyme deficient cells. Junctions between the 3' end of the provirus and the host DNA were analyzed in control cells, mutant cell lines, and complemented cell lines transduced with the HIV-based vector. Inserted abnormal sequences are lowercased. Abnormal nucleotides corresponding to the GT dinucleotides processed by integrase are presented in bold. Partial primer binding site (PBS) sequences are underlined. Squares indicate the location of micro-homologies to the GT dinucleotides and/or PBS.