Epigenetics: a new player in the regulation of mammalian puberty

All reproductively competent adults have gone through puberty. While key genes and signaling pathways that lead to the onset of sexual maturation are known, the molecular mechanisms that determine when an individual enters puberty are only beginning to be understood. Both genetic and environmental factors determine the timing of puberty. New advances in understanding how environmentally sensitive, yet highly heritable developmental processes are regulated have come from the field of epigenetics. Of note, studies investigating the epigenetic control of the onset of puberty suggest that epigenetic repression of key inhibitory loci may play a fundamental role in the initiation of puberty. Current technologies that not only read out the DNA sequence, but also determine how the DNA is modified in response to the environment, promise new insight into how puberty is regulated, including the identification and understanding of gene regulatory networks that control the biological pathways affecting pubertal timing. Here we review the findings to date and discuss how epigenetic investigation can further our understanding of this fundamental aspect of human development.