Crispr stands for “clustered regularly interspaced short palindromic repeats”, a devilishly contrived acronym which just about sums up why it was ignored for so long. For nearly two decades after Japanese researchers first discovered Crispr in bacteria in 1987, scientists mostly dismissed it as “junk DNA”.
In fact, the apparently nonsensical sequences within Crispr, which were repeated in palindromic order (the same backwards as forwards), did have a purpose and were far from junk. About six years ago, scientists discovered that these DNA sequences matched the genetic sequences of various viruses that attack bacteria, which led to the discovery of a sophisticated bacterial immune system.
Far from being junk, Crispr was actually a way of storing the genetic information of an invading virus in the form of a palindromic DNA sequence. The bacteria used this genetic memory to target the viral...