DNA probe

• What is a dna probe

  A short single stranded section of DNA that has some sort of label attached to it
• what are the 2 types of dna probe

  1. radioactively labelled with isotope 32 p. identified with photographic plate
  2. fluorescently labelled probes identified when they emit light
• how do probes identify genes

  has bases complimentary to the DNA sequence

  DNA separated into 2 strands

  Mix seperated strands with a probe which binds to complimentary bases

  site at which the probe binds can be identified by the radioactivity or the fluorescence that the probe emits
• DNA fingerprinting- process of southern blotting

  1. DNA fragments on gel
  2. Placed in alkali
  3. Nylon sheet placed on gel
  4. Nylon peeled off
  5. Probes added
  6. Radioactive probes detected by photographic film