The study by researchers at the University of Edinburgh sheds light on the process, known as DNA transposition, in which shifted genes have a significant effect on the behaviour of neighbouring genes. In the human genome, rearrangement of antibody genes can enable the immune system to target infection more effectively.

The research identifies how the enzyme is able to cut out a section of DNA and reinsert it elsewhere in the genome. The study, published in the journal Cell, was funded by the Wellcome Trust and the Medical Research Council.

The cut-and-paste property of shifted DNA is now being used to develop tools for scientific research and medical applications. Learning more about transposition could help scientists understand how to control the process and speed the development of gene therapies - which introduce into cells genes with beneficial properties that, for example, can fight hereditary diseases or cancer.

Reputedly junk DNA, which accounts for almost half of the human genome,  is now emerging as useful material in a cut-and-paste mechanism, can lead to beneficial changes in cells. A VIB group of Eu-US team of scientists recently found that stretches of tandem repeats influence the activity of neighbouring genes.

The repeats determine how tightly the local DNA is wrapped around specific proteins called ‘nucleosomes’, and this packaging structure dictates to what extent genes can be activated.

Dr Julia Richardson (right) of the University of Edinburgh's School of Biological Sciences, who led the study, said: "By forming a picture of the enzyme that causes DNA to shift, and discovering how this works, we understand more about how these proteins could be adapted and controlled. This may one day enable genes to be pasted into cells exactly where they are needed - which could be of enormous benefit in developing gene therapies."