Based on differential age distributions, KC subjects who were 15–29 years old (y/o) and 30–45 y/o had lower GnRH concentrations (67.3 ng/mL, IQR 50.8–86.2 ng/mL and 66.6 ng/mL, IQR 54.0–87.4 ng/mL, respectively) compared to age-matched controls (155.1 ng/mL, IQR 79.8–177.2 ng/mL and 98.3, IQR 72.3–203.3 ng/mL, respectively, 15–29 y/o p < 0.0001, 30–45 y/o p < 0.0001, Figure 1C). The gene discussed is GNRH1; the disease is keratoconus.