ESR2 and polycystic ovary syndrome: The results of meta-analysis suggested that ESR2 rs4986938 was not associated with increased or decreased risk of PCOS (Figure 4): Allele model (A versus G): OR=1.06 95%CI 0.81–1.38, I2 = 70%; Dominant model (AA+GA versus GG): OR=1.10 95%CI 0.77–1.57, I2 = 72%; Recessive model (AA versus GG+GA): OR=1.08 95%CI 0.87–1.35, I2 = 0%; Heterozygote model (GA versus GG): OR=1.07 95%CI 0.75–1.53, I2 = 68%; Homozygote model (AA versus GG): OR=1.10 95%CI 0.87–1.40, I2 = 28%.