Emerging evidence shows that MicroRNAs can regulate gene expression in both normal and disease states by direct targeting of the messenger RNA and inhibition of its translation to a protein, and/or by interfering with the epigenome [32] miRNA-320 act through its target ET-1 and inhibit IR in patients with PCOS through IRS-1 regulating the ERK1/2 signaling pathway and control pathways involved in follicular maturation [33]. This evidence concerns the gene IRS1 and polycystic ovary syndrome.