A concatemer of sleeping beauty transposable elements each consisting of the inverted repeat direct repeat sequence specific for sleeping beauty transposase flanking splice acceptor sites and poly A signals in both orientations. Between the splice acceptor sites is 5' long terminal repeat sequence from the murine stem cell virus followed by a splice donor site. This construct can create both loss-of-function and gain-of-function mutations. In line 68 the concatemer is integrated into chromosome 15. Around 25 copies of the construct are integrated in this line and the construct is unmethylated. (J:99991)