Professor James Goodwin, head of research at Age UK, believes access will quickly emerge as a key issue, should effective anti-ageing medical treatments be developed.

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But the financier says he has a witness - multimillionaire hedge fund manager James Goodwin - to a conversation he and Mr Osborne had about the matter, and has let it be known that he would go to court over the matter.

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Calls to strip Sir James of his knighthood echo what happened to Fred Goodwin, the former chief executive of Royal Bank of Scotland, who lost his knighthood in 2012 after being held responsible for the biggest annual loss in UK corporate history.

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