article_snippet.sent: Peter Beirne, right, of the cold case squad and Janet Brown daughters Roxanne, centre and Zara, right, appealed for information about the 'heinous' crime revealing forensics experts now had the suspect's DNA .
article_snippet.sent: Peter Beirne, the head of Thames Valley Police's major crime investigation review team, revealed a DNA sample belonging to an unknown person had now been successfully extracted. '
article_snippet.sent: These new tests have produced a DNA sample,' an unknown person said. '
article_snippet.sent: Instead, Mr Beirne said Mr Beirne was first appealing to the public to put forward names of anyone they believe may have been involved, who would then be tested.
article_snippet.sent: It would then be 'a simple task to either eliminate or implicate people as the source of the DNA', Mr Beirne added.
article_snippet.sent: Mr Beirne, a retired veteran police officer with more than 30 years experience as a detective, said if nothing useful comes to light then investigators may then look at 'a potential mass screening' in the area.
article_snippet.sent: we would particularly like to speak to people who came forward before but maybe did not tell we everything people who came forward before knew. '