The DNA photofit
Amazing breakthrough means police can tell suspect’s colour, height and even age – from a tiny speck of blood
POLICE are now able to build up a detailed picture of a suspect from the smallest speck of blood left at a crime scene thanks to an extraordinary DNA breakthrough.
New advances in the technology mean detectives will know if an offender is black or white, the colour of their hair and eyes, their height and age – even if there are no witnesses to the crime.
Until now, investigators have only been able to match genetic material to records of criminals already in the national database, but the innovation will produce a ‘DNA photofit’ describing the offender.
Dr Denise Syndercombe-Court, a forensic genetics expert at King’s College London, said: ‘The new technologies raise the possibility that we won’t need an actual eyewitness to a crime in order to produce a picture of how the suspect looks.
‘Instead, investigators will be able to generate a DNA photo detailing a suspect’s characteristics, biological age and geographical ancestry.’
She said the value to police is ‘enormous’ in narrowing down the pool of suspects and eliminating the innocent. ‘We are now in the moment of glimpsing a brilliant new future of DNA analysis,’ she added.
Each test costs about £700 to carry out and can take up to ten days for the analysis to be done.
The breakthrough comes thanks to the Human Genome Project, which identified all the genes in human DNA, meaning scientists can single out the sequences that determine individual characteristics. Academics and private companies are now developing tests that focus on indi- vidual areas such as eye colour. In the past year, King’s College London, working with the Metropolitan Police, has helped on a ‘handful’ of criminal cases to identify the geographical background of suspects based on DNA samples. They are currently achieving success rates of more than 85 per cent.
King’s can also work out a suspect’s eye colour but has not yet used this in a forensic case. The university is working on identifying other ‘externally visible characteristics’ with colleagues across Europe.
Within two years, academics hope to have perfected the ‘next generation’ of sequencing, which should speed up analysis, increase accuracy and bring down the cost.
Gary Pugh, director of forensic services at Scotland Yard, said: ‘By a combination of looking at different parts of the DNA molecules, you could get things like face shape, physical characteristics and baldness as well, because it’s genetic. You can even distinguish between identical twins because there will be mutations and very slight differences.’
However, the implications of the ‘extraordinary’ amount of information provided by the new tests could prove controversial.
A quango called the National DNA Database Ethics Group will study the issue. It said an ‘ethical framework’ will be developed to consider the use of data and ‘how might the right of individuals be balanced against the rights of the state’.
Researchers say they will only study visible physical characteristics and not look into sensitive, private data such as if a person has a particular disease or a high likelihood of developing conditions such as dementia in later life.