The human-viral junctions of integrated adenovirus type 5 (Ad5) DNA in 293 cells have been cloned and sequenced. The Ad5 sequences extend from nucleotides (nt) 1 to 4344 and are located in the pregnancy-specific beta-1-glycoprotein 4 (PSG 4) gene. This maps the insertion of Ad5 DNA to human chromosome 19 (19q13.2). The Ad5 sequences are represented as a single collinear insertion of viral DNA with no rearrangements. There were 19 bp of PSG4 DNA deleted at the site of insertion and an extra 3 nt (GTC) at the left viral/cellular junction. A short patch of homology between viral DNA and PSG4 DNA (6 nt with 1 mismatch) was present at the right junction.