Required for the transport of GPI-anchored proteins to the plasma membrane (PubMed:24367057). Probable acetyltransferase, which acetylates the inositol ring of phosphatidylinositol during biosynthesis of GPI-anchor. Acetylation during GPI-anchor biosynthesis is not essential for the subsequent mannosylation and is usually removed soon after the attachment of GPIs to proteins (By similarity). Glycolipid biosynthesis; glycosylphosphatidylinositol-anchor biosynthesis. The disease is caused by variants affecting the gene represented in this entry. Belongs to the PIGW family.