The small fragments of a long DNA molecule that are used to detect presence of specific gene or DNA sequence in biological system are known as ‘DNA probes’.
They are produced by following methods:
By using automated DNA synthesizers, specific sequences of DNA probes can be produced.
They are also synthesized by biological enzymes, using template DNA.
They are also present in viral DNA and may be multiple in bacteria.
Their applications in commercial areas are to diagnose infectious disease, identify food contaminants and many more.