PPP1R21 and endometriosis: The SHBG-impacts of 7 SNPs from 9 analyzed loci such as rs17496332 (A > G) PRMT6, rs780093 (C > T) GCKR, rs10454142 (T > C) PPP1R21, rs3779195 (T > A) BAIAP2L1, rs440837 (A > G) ZBTB10, rs7910927 (G > T) JMJD1C, and rs8023580 (T > C) NR2F2 interacting with each other have been endometriosis-associated.