Clinicians have continued to use a cutoff GnRH-stimulated LH value >5 IU/L for the diagnosis of precocious puberty (37), the same value traditionally used LH-RIA, without taking into consideration the differences between RIA and immunometric assays, between different immunometric assays, and the likely potency difference between GnRH and GnRHa (98). Here, PLOD1 is linked to precocious puberty.