Enhancer (genetics)

In genetics, an enhancer is a short region of transcription factors) to enhance transcription levels of genes (hence the name) in a gene-cluster. An enhancer does not need to be particularly close to the genes it acts on, and need not be located on the same chromosome.^[1] The structure of the chromatin complex of DNA is folded in such a way that although the DNA is far from the genes in nucleotides, it is geometrically close to the promoter and gene. This allows it to interact with the general transcription factors and polymerase II. An enhancer may be located upstream or downstream of the gene that it regulates. However, an enhancer does not need to be located near to the introns. An enhancer's orientation may even be reversed without affecting its function. Furthermore, an enhancer may be excised and inserted elsewhere in the chromosome, and still affect gene transcription. That is the reason that intron polymorphisms are checked though they are not transcribed and translated.