要約
This locus represents an enhancer region that can regulate expression of both the non-coding H19 gene and the gene encoding insulin-like growth factor 2 (IGF2). These genes, which are located in a head-to-tail arrangement in opposite orientations, have imprinted expression patterns, where the H19 gene is expressed only from the maternal allele, and the IGF2 gene is expressed only from the paternal allele. This enhancer region is located downstream of the H19 gene. On the maternal allele, the ability of this enhancer region to regulate the more distal IGF2 gene is blocked by an imprinting control region (ICR), which is located between the H19 and IGF2 genes. On the paternal allele, the enhancer-blocking function of the ICR is disabled via DNA methylation, thus allowing this enhancer region to activate the IGF2 gene. Mutations in this enhancer region are associated with Silver-Russell syndrome and growth retardation. [provided by RefSeq, Feb 2015]
