Transgenic construct used to study the Fab-7 element. Contains a UAS-driven lacZ reporter and a w[+] minigene (transcription of both these genes is in the same orientation). A 219bp Fab-7 fragment in which the three z binding sites have been mutated from YGAGYG to YGCAYG has been inserted upstream of the UAS-lacZ reporter and its effects on w expression have been analyzed.