<p>This family contains sequences expressed in eukaryotic organisms bearing high similarity to the conserved region of <taxon tax_id="7227">Drosophila melanogaster</taxon> wings apart-like protein (WAPL). The D. melanogaster WAPL protein regulates heterochromatin structure [<cite idref="PUB00016495"/>]. It is required to hold sister chromatids of meiotic heterochromatin together and is implicated in both heterochromatin pairing during female meiosis and the modulation of position-effect variegation (PEV). Although the high-sequence conservation is limited to a third of the protein sequence, a WAPL homologue has been identified in mammals. Mammalian WAPL may play a significant role in meiosis as does the Drosophila one. Human WAPL is overexpressed in invasive human cervical cancers and is often associated with cervical carcinogenesis [<cite idref="PUB00016544"/>, <cite idref="PUB00043751"/>].</p>