GNRH1 and peripheral precocious puberty: Depending on whether the hypothalamic-pituitary-gonadal axis (HPGA) occurs or not, precocious puberty is classified as central precocious puberty (CPP) with the HPGA occurring driven by early increased gonadotropin-releasing hormone (GnRH) secretion, which accounts for roughly 80% [4], and peripheral precocious puberty (PPP) which is independent of GnRH secretion.