Catalytic subunit of the ethanolamine phosphate transferase 2 complex that transfers an ethanolamine phosphate (EtNP) from a phosphatidylethanolamine (PE) to the 6-OH position of the second alpha- 1,6-linked mannose of a 2-acyl-6-[6-phosphoethanolamine-alpha-D- mannosyl-(1->2)-alpha-D-mannosyl-(1->6)-2-phosphoethanolamine-alpha-D- mannosyl-(1->4)-alpha-D-glucosaminyl]-1-(1-radyl,2-acyl-sn-glycero-3- phospho)-1D-myo-inositol (also termed H7) intermediate to generate a 2- acyl-6-[6-phosphoethanolamine-alpha-D-mannosyl-(1->2)-6- phosphoethanolamine-alpha-D-mannosyl-(1->6)-2-phosphoethanolamine- alpha-D-mannosyl-(1->4)-alpha-D-glucosaminyl]-1-(1-radyl,2-acyl-sn- glycero-3-phospho)-1D-myo-inositol (also termed H8) and participates in the eleventh step of the glycosylphosphatidylinositol-anchor biosynthesis. {ECO:0000269|PubMed:33763700, ECO:0000269|PubMed:34113002, ECO:0000305|PubMed:15632136, ECO:0000305|PubMed:26996948}. This is the function of Ensembl gene identifier ENSG00000174227 (PIGG, phosphatidylinositol glycan anchor biosynthesis class G (EMM blood group)).