Fourteen genes/ SNPs were associated with endometriosis risk in more than one article (chromosome 1, 2, 6, 7, 9 and 12; WNT4, GREB1, FN1, IL1A, ETAA1, RND3, ID4, NFE2L3, CDKN2B-AS1, VEZT, SYNE1, FSHB, ESR1, ARL14EP). This evidence concerns the gene IL1A and endometriosis.