Genetic fingerprinting

• What are the non-coding sections of DNA called?

  Variable number tandem repeat (VNTRs)
• What is the process of lengthening the DNA fragments?

  Gel electrophoresis
• What is gel electrophoresis?


  DNA fragments are placed into a well of gel and a voltage is applied across

  Smaller fragments travel further so DNA fragments of different lengths are separated
• What are the 5 processes of genetic fingerprinting?

  • Extraction
  • Digestion
  • Separation
  • Hybridisation
  • Development
• What happens during extraction?

  DNA is extracted from the sample
• What is digestion?


  Restriction endonucleases cut DNA into fragments
• What is separation?


  Fragments are separated by gel electrophoresis and moved to the nylon membrane
• What is hybridisation?


  DNA probes label the fragments
• What is development?


  Radioactively labelled DNA fragments placed onto X-ray film, which reveals where the DNA probes are attached
• What are some uses of genetic fingerprinting?

  • Paternity tests
  • Forensic science
  • Medical diagnosis
  • Plant and animal breeding