The greatest contribution to the susceptibility to endometriosis (Figure 6; it is a network of paired interactions that form proteins functionally related to 7 endometriosis-associated loci and 115 proxy variants) came from such paired protein interactions as GTF2A1L-STON1 (coefficient [score] of the protein interaction—0.992), JMJD1C-REEP3 [0.901], C2orf16-ZNF512 [0.777], FSHR-LHCGR [0.698], KRTCAP3-NRBP1 [0.626], PPP1R21-STON1 [0.610], C2orf16-GPN1 [0.610], and KRTCAP3-ZNF512 [0.604)]. This evidence concerns the gene PPP1R21 and endometriosis.