Transgenic construct used to examine the properties of the Mcp element from the bithorax complex. Comprises a 817bp SalI-XbaI fragment (1154-1971) of the Mcp element, spanning the DNAse I-hypersensitive region, followed by a fragment of the y gene, including the whole y intron (this includes the tce and ble enhancer regions), and a w[+] minigene.