These are synthetic single-stranded DNA sequences that are, among other things, capable of cutting nearby DNA strands in specific places.

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The message itself is copied into a single-stranded messenger molecule which carries it to the protein-making parts of the cell, where it is translated.

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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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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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