2.5kb Bari1 element is inserted at the 3' end of Cyp12a4. The transcript produced is 1.7kb long and contains 18 nucleotides derived from Bari1 in place of the 3' end of the 1.9kb Cyp12a4 transcript found in wild type. The amount of transcript produced in the Cyp12a4Bari1-1386 mutant is about tenfold higher than in wild type.
Flies carrying Cyp12a4Bari1-1386 show no significant difference in DDT resistance compared to control flies.