DNA fingerprinting

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DNA fingerprinting
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• In 1984, Professor Sir Alec Jeffreys discovered
  that certain parts of your DNA (not the genes but
  other bits called VNTRs) are very variable within
  the population.
• However, these VNTRs are similar among related
  individuals.
• He used this to make DNA profiles (genetic
  fingerprints) of people.
• DNA fingerprinting is a way of comparing DNA
  samples to see if they come from the same person,
  from two different people or from related people.
• It works by screening for certain DNA sequences
  which are found in some individuals but not
  others.

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Uses of DNA fingerprinting

• In forensic science DNA (from hair, skin
  flakes, blood, semen, etc.) taken from a crime
  scene is compared with a DNA sample taken from a
  suspect.
• It has led to many criminal convictions for rape
  and murder and has also shown if a person is
  innocent of a crime, sometimes after being
  wrongly convicted.
• In 1986, Colin Pitchfork was the first criminal
  convicted in the UK using DNA fingerprinting.

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DNA fingerprint results from a rape
investigation. Suspect 1s DNA matches that of
the sperm found in the victim.
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Uses of DNA fingerprinting

• In paternity and maternity tests to check if a
  man or woman and a child are father/mother and
  son/daughter.
• In a landmark court case, Alec Jeffreys produced
  DNA profiles to prove to immigration officials
  that a girl was indeed the daughter of a mother
  living in the UK.
• To establish family relationships for example,
  the remains of some bones found in Russia were
  shown to be those of the Russian royal family
  executed in 1917.