Cambridge University scientists say they have seen four-stranded DNA at work in human cells for the first time.

BBC: 'Quadruple helix' DNA seen in human cells

Four-stranded DNA, a database of alien planets, a new super-chemical to kill hospital bugs and a byzantine gamma-radiation blast.

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This revealed the four-stranded DNA arose most frequently during the so-called "s-phase" when a cell copies its DNA just prior to dividing.

BBC: 'Quadruple helix' DNA seen in human cells

DNA. This molecule is a double-stranded helix made from four different types of sub-molecule.

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