Involved in GPI-anchor biosynthesis (PubMed:33386993). It acts through the transfer of ethanolamine phosphate to the third mannose of GPI. Glycolipid biosynthesis; glycosylphosphatidylinositol-anchor biosynthesis. Forms a complex with PIGG and PIGO. PIGF is required to stabilize PIGG and PIGO. The disease is caused by variants affecting the gene represented in this entry. Belongs to the PIGF family.