A portion of the per 3'UTR present in per+t13.2 has been replaced with a KpnI-Bsu36I fragment containing the corresponding per 3'UTR sequence from the most common SNP1/SNP2/Af1/Af3 haplotype (C/A/T/T) for flies from tropical locations in Australia. The exchanged fragment extends from the stop codon to approximately 70bp upstream of the site for 3' cleavage/polyadenylation. Three copies of the Tag:FLAG epitope have been inserted just upstream of the translation stop codon.