Results: Forty-minute post-injection samples had the greatest frequency of “peaking luteinizing hormone (LH)” (p<0.001) in the diagnostic tests when the cut-off value was taken as 5 IU/L for LH, 40th minute sample was found to have 98% sensitivity and 100% specificity in the diagnosis of precocious puberty, while the sensitivity and specificity of the 20th minute sample was 100% in the assessment of pubertal suppression. The gene discussed is PLOD1; the disease is precocious puberty.