Among the 10 boys, 8 had LH and FSH peaks below 1 U/L after the GnRH test; 2 had LH/FSH peaks of 5.4/4.3 and 8.4/3.7 U/L, plasma testosterone concentrations that remained below 0.5 ng/mL, and micropenis (one) and/or cryptorchidism (both). Here, PLOD1 is linked to cryptorchidism.