In patients with PCOS-IR, insulin tyrosine phosphorylation is weakened and serine phosphorylation is enhanced, thereby weakening the combination of insulin receptor substrate with the upstream protein PI3K of the signal transduction pathway, then inhibiting the activity of cytoplasmic signal transduction pathway and finally induce IR, or on the other hand, IR is induced by genetic mutations in the insulin receptor on tissue membranes, or defects in IRS-1 or glucose transporters. This evidence concerns the gene IRS1 and polycystic ovary syndrome.