Miss Pearman's body was found by a lorry driver at about 3.50am. She was last seen alive in Rouen Road, Norwich, at 1.15am the same day.
At the time of the initial investigation, DNA samples were taken and loaded onto the national database but no match has yet been found.
Over the years, more than 4,000 people have been interviewed and hundreds of men provided DNA samples for testing.
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