The HIV retrovirus, in particular, is a single-stranded RNA virus that duplicates itself in a host cell by converting its genetic code into double-stranded DNA that is then inserted into the host cell.

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

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One way in which this occurs is through "RNA interference", which involves the introduction of double-stranded RNA molecules.

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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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Also, repatriation of corporate earnings stranded abroad to avoid double taxation may be a potential windfall.

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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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