Specific genetic alterations (MKRN3, KISS1, KISS1R, DLK1, GPR54, and also other syndromes), central nervous system lesions (e.g., hypothalamic hamartoma) and social and environmental stressors (e.g., adoption or endocrine disruptors) are major drivers of CPP, although the majority of patients with CPP have no identified etiology and are labeled as idiopathic CPP. This evidence concerns the gene DLK1 and central precocious puberty.