IL1A and endometriosis: The intergenic SNP rs6542095 near IL1A is ranked second in the list of 22 variants, and the effect allele T is strongly associated with decreased risk (OR = 0.89; 95% CI = 0.85–0.94; P = 1.7 × 10−6; Phet = 0.75) of endometriosis (Table 2), with slightly stronger association (OR = 0.88; 95% CI = 0.84–0.93; P = 8.9 × 10−7; Phet = 0.56) with Grade B endometriosis (Supplementary Table S2).