According to the study, the DNA samples and the pressure to gain a conviction can be highly subjective and prone to error and can lead to bias.
The Daily Mail, sent a sample of DNA from a real crime scene to 17 experienced analysts in a US lab. The experts" differing results cast doubts over the technique"s reliability.
The sample, from a gang rape, had already been used to convict a man but only one of the 17 scientists came to the same conclusion.
University College London scientist, Itiel Dror, who helped in the investigation, said, "it is time DNA analysts accept that under certain conditions, subjectivity may affect their work."
The chances of two people having the same DNA fingerprint are between 800,000 and one billion to one. But there are concerns that increasing reliance on tiny samples of blood and saliva, often from more than one person, leaves interpretation open to the scientist"s judgment.
"Profiling is generally seen as infallible and it is always able to get its man. But DNA profiling is far from perfect," the New Scientist added.