The terms sense and antisense were coined by Paul Zamecnik to show the complementary, double-strand nature of DNA. One strand consisted of alternating patterns of the four nucleotides that make up DNA adenine, cytosine, guanine and thymine and it could be read in order.

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To Dr Baselt this suggested that tiny magnetic particles might be attached to molecules using either antibodies (which will bond to proteins, sugars and so on) or single-stranded DNA (which will bond to a complementary DNA strand to form the famous double helix).

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He says apprehensions here are down 95 percent, from 100, 000 a year to 5, 000 a year, largely because the single strand of cable marking the border was replaced by double and in some places, triple fencing.

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And if sense and antisense should meet, the resulting double-stranded molecule no longer works, so the protein the sense strand encodes is not made any more.

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On the double helix that comprised the Os in Google, a small section of a strand crossed another at the wrong spot.

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