Rekombinationsmarkern

Rekombinationsmarkern, also known as recombination markers or selectable markers, are DNA sequences used in molecular biology to identify cells that have successfully incorporated foreign DNA into their genome. These markers typically confer a specific trait upon the host cell, such as resistance to a particular antibiotic or the ability to synthesize a nutrient that the cell cannot produce on its own.

The principle behind using recombination markers is to create a selective pressure in the environment where the genetically modified cells are grown. For example, if a gene conferring antibiotic resistance is used as a recombination marker, then only cells that have successfully integrated this gene will survive when exposed to that antibiotic. Cells that have not undergone the genetic modification will be killed by the antibiotic, allowing researchers to isolate and propagate the desired genetically modified cells.

Common examples of recombination markers include genes for resistance to antibiotics like ampicillin, kanamycin, or hygromycin, as well as genes involved in metabolic pathways, such as the HIS3 gene, which allows cells lacking histidine to synthesize it. The choice of recombination marker depends on the host organism and the experimental setup. Careful selection of markers is crucial to avoid interference with the intended function of the introduced DNA or the host cell's metabolism. Recombination markers are a fundamental tool in genetic engineering, enabling efficient screening and selection of transformed organisms.