Then Pitchfork had Kelly submit his own blood for him. Months later his ploy was discovered by law enforcement when a resident came forward after hearing a conversation at a local pub in which Kelly admitted that he was paid by Pitchfork to have his blood tested.
This led to the arrest of the twenty seven-year old Pitchfork. It was a perfect match. Instead of going to trial, Pitchfork pled guilty to both rapes and murders. In , Pitchfork became the first person in the world to be identified, captured and successfully prosecuted as a result of DNA evidence. The court allowed me to let the family know we had proved their case, and I shall never forget the look in the mother's eyes. The first paternity case came hot on the heels of that dispute and then - in Sir Alec's words - "the flood gates opened".
At this point, all cases were dealt with by the Leicester laboratory. Sir Alec was a research fellow for the Lister Institute who gave him funding to take on another technician to enable them to run tests on a larger scale and for two years his was the only laboratory in the world doing this work.
He describes it as 'exciting but exhausting', and had no regrets when ICI now AstraZeneca were granted a licence to set up Cellmark and put the research on a commercial level.
At this time the forensic implications of genetic fingerprinting were emerging. The original process proved to be inadequate for this, and so from Sir Alec and his team developed a variation which they called "genetic profiling" for forensic use. Again, its first application caught the public mood. Two young girls were raped and murdered in the Enderby area of Leicestershire. A man who had been arrested had confessed to one murder but not the other, and the police decided to use genetic profiling, thinking to prove him guilty of both cases.
Against all expectation he was found to be innocent of both. Then the hunt was on to find a genetic profile among the entire male population of the area that matched samples taken from the two victims.
No match was found, until Colin Pitchfork was overheard boasting of how he had persuaded a friend to give a sample on his behalf. The case was solved. How did Sir Alec feel when Pitchfork was finally convicted? Also, here was a serial killer in the region who knew what I was doing and where I worked and where my family lived. That feels very uncomfortable so on a personal level it was a great relief when he was trapped.
The original technology used to catch Pitchfork is now largely obsolete, though still in use in some laboratories around the world. But the techniques have been speeded up and simplified. In the UK we now have a national database of 2. While there is some concern amongst civil rights activists, Sir Alec feels it would be "criminally irresponsible" not to maintain the database and would mean that rapists and murderers who are now identifiable would be able to continue unstopped.
However, he does take civil rights seriously and is concerned with the fact that suspects' DNA profiles are also being stored on police records. He sees this as discriminatory, though notes that this potential infringement of civil rights of minority groups would largely disappear if everybody was "fingerprinted".
On average, about The remaining percentage is what makes us unique unless you are an identical twin! Although this might sound like a small amount, it means that there are around three million base pairs that are different between two people.
These differences can be compared and used to help distinguish you from someone else. Minisatellites are short sequences base pairs long of repetitive DNA that show greater variation from one person to the next than other parts of the genome.
The first minisatellite was discovered in DNA fingerprinting is a technique that simultaneously detects lots of minisatellites in the genome to produce a pattern unique to an individual.
This is a DNA fingerprint. The probability of having two people with the same DNA fingerprint that are not identical twins is very small. Just like your actual fingerprint, your DNA fingerprint is something you are born with, it is unique to you. How was the first DNA fingerprint produced? This resulted in thousands of pieces of DNA with a variety of different lengths.
These pieces of DNA were then separated according to size by a process called gel electrophoresis : The DNA was loaded into wells at one end of a porous gel, which acted a bit like a sieve. The Home Office called in Jeffreys and, after a detailed explanation by him, agreed to drop the case. But the look on her face when I told her, the relief - it was a magical moment.
I realised then that we were on to something of real use. We had reached out and touched someone's life. Over the next decade, DNA fingerprinting was used to test more than 18, immigrants who had been refused entry into the UK.
The next two years were "simply insane", adds Jeffreys. He was inundated with calls from families, mostly of Bangladeshi or Pakistani origins, who had been caught up in immigration disputes. Use your DNA fingerprinting technology to prove he killed both girls, they asked him. Only a limited number of repeated regions are counted, a technique that is quicker to use and requires smaller samples.
It was a perfect opportunity to show off the forensic value of genetic fingerprinting, Jeffreys realised, and, as the tests were being completed, he worked through the night to finish them off as quickly as he could.
He pulled the film from its developing tank. The film was covered in black bands, which showed that the semen from both girls came from the same man, but that Buckland's DNA was completely different. He was not the murderer, the tests indicated.
The police's response was terse and Anglo-Saxon. For his part, the geneticist began to worry that the whole concept of DNA profiling was "up the spout" and that there were things going on biologically that science still did not understand. Then the Home Office repeated the tests and produced the same results as Jeffreys. In the end, the police accepted Buckland's innocence and on 21 November , at Leicester Crown Court, he was cleared of the girls' murders.
Thus the first use of DNA fingerprinting in a criminal case was to help free an innocent man. In the end, that perpetrator was caught by a combination of DNA science and "good old-fashioned coppering", as Jeffreys puts it. In January police asked all local men between 17 and 34 to submit blood for DNA testing in order to eliminate them from their inquiries.
By September, 4, had provided samples without success - until a chance remark transformed the investigation. In a pub one day a local man admitted to his mates he had provided blood on behalf of a friend, Colin Pitchfork.
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