Multivariate analysis of all studied hormonal and instrumental parameters of PCOS in adolescents revealed as the most essential: AMH level > 7.20 ng/mL, FAI > 2.75, androstenedione > 11.45 ng/mL, total T > 1.15 nmol/L, LH/FSH ratio > 1.23, and the volume of each ovary > 10.70 cm3 (for each criterion sensitivity ≥ 75.0–93.0%, specificity ≥ 83.0–93.0%). This evidence concerns the gene PLOD1 and polycystic ovary syndrome.