Timeline Of DNA

1953 – James Watson and Francis Crick identify structure of DNA.


Watson and Crick pose with double helix

1984 – Alec Jefferys discovers Restriction Fragment Length Polymorphism (RFLP). RFLP breaks DNA into pieces and separates them using gel electrophoresis.

Injecting DNA into gel

1985 – UK police use first DNA profiling—a double murder investigation in a small Leicestershire town. Sir Alec Jeffreys concluded that a suspect held by police was not the attacker. However, in 1987, Jefferys conducted additional testing from a pool of 5,000 men and correctly identified the killer in the double murder. In 1988, the killer, Colin Pitchfork, was sentenced to life in prison.

1986 – Kary Mullins discovers Polymerase Chain Reaction (PCR), sort of a DNA copy machine used to replicate DNA. Mullis, a 1993 winner of the Nobel Prize in chemistry, had expressed an affinity to LSD and was subsequently removed as a witness in the original O.J. Simpson trial. The defense figured there was enough controversy in their case as it was.

Kary Mullis

Kary Mullis

PCR machine

1987 – Robert Melias is the first person convicted of a crime (rape) in the UK based on DNA evidence.

1987 – Tommy Lee Andrew is the first person convicted of a crime (rape) in the U.S. based on DNA evidence.

1988 – Timothy W. Spencer is the first person in the U.S. to be convicted and sentenced to death based on DNA evidence. Spencer was on probation and living in a halfway house when he raped and killed his victims.

Timothy W. Spencer

1989 – Gary Dodson is the first person in the U.S. to have a conviction overturned based on DNA.

1994 – Timothy W. Spencer, The Southside Strangler, is the first person executed in the U.S. because of a conviction based on DNA evidence.

1995 – The first DNA database begins operation in the UK.

1996 – Mitochondrial DNA is used in court for the first time. Mt DNA was compared and used in a trial to convict Paul Ware for the rape and murder of a child. DNA in a hair found on the body matched Ware’s DNA.


1998 – The FBI begins a national DNA database.

* Things Writers Should Know About DNA

5 replies
  1. JanW
    JanW says:

    Thanks, Lee. We’ve recently had a situation where DNA based cases have been overturned due to problems in a local lab:

    Police put ban on DNA evidence
    * Milanda Rout and Rick Wallace
    * From: The Australian
    * December 10, 2009 12:00AM

    POLICE forces across the country could have their DNA evidence thrown into doubt after Victoria Police discovered a systematic breakdown in how it interpreted DNA samples and warned that other jurisdictions would face the same problem.

    Then the ban was removed:
    Victoria lifts ban on DNA evidence

    * From: AAP
    * January 12, 2010 2:55PM

    A BAN on DNA evidence in Victorian courtrooms has been lifted following the adoption of a national standard in forensic laboratories across the country.

    Victoria Police had stopped using DNA evidence on December 9 to fix an error in how DNA was being interpreted in its forensic labs.

    The ban affected at least six criminal cases and came two days after a rape conviction was overturned because of a contaminated DNA sample.

    A day later, a scathing ombudsman report was released detailing mismanagement within forensic laboratories.

    Might be something in there that the writers can use.


  2. Dave Swords
    Dave Swords says:

    Several years ago, I read Joseph Wambaugh’s “The Blooding,” about the 1986 DNA case in England.


  3. Pat Marinelli
    Pat Marinelli says:

    Thanks, Lee, for another wonderful post to help us writers get our facts straight when plotting our stories ideas.

    I have to say your blog is the first place I go now to find answers needed when writing.

  4. Falcocop
    Falcocop says:


    DNA….something I have used a number of times during my career and on occasion still do if it is needed for the Identificationof bodies. I have also used it in Birds of Prey to prove or disprove parentage in Wildlife Crime cases. I understand I also had the privilege of being the first UK Cop to prove through DNA that the Falcon reported as being stolen, and found hidden at a friends house, was in fact not stolen and was subject of an Insurance Fraud. Although the owner claimed it was another bird, DNA testing proved his claim was wrong.


    “I see dead people”

Comments are closed.