Experiments conducted in animal models as well as equivalent natural situations in humans, i.e., pregnancy in PCOS or congenital adrenal hyperplasia, demonstrated that exposure to androgen excess during the foetal life and infancy determines the PCOS features in adult life, with LH hypersecretion, oligomenorrhoea, polyfollicular enlarged ovaries, insulin resistance, abdominal obesity, impaired insulin response to glucose and dyslipidemia [11-17]. The gene discussed is INS; the disease is Insulin resistance.