Recombinant DNA is a type of DNA that is artificially created by inserting a strand or more of DNA into a different set of DNA. Recombinant DNA is used in genetic modification to create completely new organisms by adding artificial bits or bits of DNA from other organisms to an existing creature. Recombinant DNA is often referred to as rDNA for short.

The technique for making recombinant DNA was first developed in the early-1970s by Herbert Boyer and Stanley Norman Cohen. Their original paper described a method to use recombinant DNA to create transgenic bacteria. Their work was built on the work of Daniel Nathans, Hamilton Smith, and Werner Arber, who discovered restriction endonucleases. In 1978 the three were awarded the Nobel Prize for Medicine for this discovery.

At its most basic, recombinant DNA is just putting strands of DNA together that wouldn’t otherwise appear together. These could simply be multiple strands of cloned DNA from the same organism, combined to create something new or different. Usually, however, in the popular mind recombinant DNA is used to refer to so-called chimeric plasmids. These are DNA molecules which contain strands from multiple animals, named after the mythological creature which contained various animal parts.

Once these plasmids have been created, they are introduced to an organism through a vehicle. The most common vehicles for recombinant DNA are the E. coli bacteria and subsequent derivatives. Once introduced, these plasmids replicate and can make actual changes in the organism itself manifest.

Other methods of introducing recombinant DNA bypass using a vehicle entirely. In the method known as microinjection, the new DNA is actually injected right into the nucleus of a cell, rather than having a bacterium introduce it. In the method known as biolistics, cells are hit with extremely high speed particles, usually tungsten or gold, which are coated with DNA that then essentially sticks to the cell.

Recombinant DNA is used to try to introduce very specific features into crops, bacteria, and animals, usually to make them more beneficial to humans, although sometimes simply as a demonstration of a technique, or sometimes as an artistic statement. Some well-known uses of recombinant DNA are to make crops drought resistant, to create new vaccines, such as the newest Hepatitis B vaccine, to make crops naturally pest resistant, and the infamous GloFish, which were zebrafish that were made fluorescent.

Recumbent DNA is a common misspelling of recombinant DNA. Recumbent DNA String Exponent is also the name of an album by the band Endymion. Endymion is a small band from the Netherlands, with members Bart Revier, Jelle Neys, and Bas Lint. Endymion has released more than twenty singles and albums since 1998. Recumbent DNA String Exponent was their first album, released in early 1998 on the Supreme Intelligence label. Recumbent DNA String Exponent has only two songs on the album: Failure on Side A, and Judge of Darkness on Side B. It is likely that the name Recumbent DNA is an intentional misspelling, playing with the sound of the word recombinant.