UASp regulatory sequences drive expression of the coding sequence of Hsap\DUX4, with the sequence starting from the second of the two potential in-frame methionines in the coding sequence (base pair 5094 relative to a KpnI site 5' to the gene), producing a protein that starts with the amino acid residues MAL. The Hsap\DUX4 sequence has been codon optimised for expression in Drosophila and is tagged at the N-terminal end with Tag:HA.