This region encompasses the proximal promoter and upstream regulatory elements of the leptin gene, including an enhancer in placental cells. The placental enhancer is derived from an endogenous retroviral long terminal repeat (LTR), and therefore represents an example of retroelement exaptation. Activity of the promoter is stimulated by hypoxia and insulin. This region is methylated and epigenetically-silenced in tissues that do not express leptin. Naturally-occuring common polymorphisms in this region (e.g. rs7799039; G-2548A) may affect activity of this promoter and correlate with obesity and other health measures. [provided by RefSeq, Jun 2016]
