Genetic and epigenetic regulation of puberty with respect to central precocious and delayed puberty

Background The onset of puberty is controlled by the complex interaction of genetic, environmental and epigenetic factors. The (re)activation of gonadotropin-releasing hormone (GnRH) neurons is the key event for the initiation of puberty.Aim This article gives an overview of the (epi)genetic factors that according to the current state of knowledge play a role in this process.Methods Review of relevant publications and review articles on central precocious puberty (CPP) and hypogonadotropic hypogonadism (HH).Results For CPP mutations in the four genes KISS1, KISS1R,MKRN3 and DLK1 have been reported. Loss-of-function mutations in the MKRN3 gene are by far the most common ones. In HH mutations have been detected in over 50 genes. The changes can be divided into mutations that influence fetal GnRH neuronal migration and function causing a delayed up to absent puberty and changes that disturb the homeostasis between activating and inhibiting signals on the GnRH neuronal network.Conclusion Various epigenetic influencing factors enable the organism to respond to extrinsic (environmental signals) and intrinsic (developmental programming) factors as a result of functional modifications of the chromatin structure and therefore lead to an adaptation process with respect to the initiation and progression of the pubertal process.