"There is a lot we don't know yet. One thought is that these quadruplex structures might be a bit of a nuisance during DNA replication - like knots or tangles that form.
"Did they evolve for a function? It's a philosophical question as to whether they are there by design or not - but they exist and nature has to deal with them. Maybe by targeting them we are contributing to the disruption they cause."
The study showed that if an inhibitor is used to block DNA replication, quadruplex levels go down - proving the idea that DNA is dynamic, with structures constantly being formed and unformed.
The researchers also previously found that an overactive gene with higher levels of Quadruplex DNA is more vulnerable to external interference.
"The data supports the idea that certain cancer genes can be usefully interfered with by small molecules designed to bind specific DNA sequences," said Balasubramanian.
"Many current cancer treatments attack DNA, but it's not clear what the rules are. We don't even know where in the genome some of them react - it can be a scattergun approach.
"The possibility that particular cancer cells harbouring genes with these motifs can now be targeted, and appear to be more vulnerable to interference than normal cells, is a thrilling prospect.
"The 'quadruple helix' DNA structure may well be the key to new ways of selectively inhibiting the proliferation of cancer cells. The confirmation of its existence in human cells is a real landmark."
|Contact: Fred Lewsey|
University of Cambridge