With the current level of diagnostic capabilities, PCOS patients may potentially benefit from genetic testing using genetic screening tests that will determine the polymorphism in the serine/threonine kinase 11 (STK11) or LKB1 and organic cation transporter 1 (OCT1) genes, respectively affecting the pharmacodynamics and the pharmacokinetics of metformin [63]. This evidence concerns the gene STK11 and polycystic ovary syndrome.