EGF and polycystic ovary syndrome: The first GWAS conducted in Chinese patients in 2011 (Fig. 1) identified three genomic regions associated with the disease.67 Additional studies66,68,69 identify 16 independent signals in 15 genomic regions associated with PCOS including signals near important reproductive hormone genes FSHR, LHCGR and FSHB. 70 The signals also include variants in or near three epidermal growth factor genes and genes associated with diabetes.40,70 As with similar studies in other reproductive diseases, the total heritability explained by GWAS identified PCOS risk SNPs is relatively low (<10%).65