The appeal follows the High Court ruling to overturn a GMC hearing's decision to remove Professor Sir Roy Meadow from the register.
Professor Meadow appeared before the GMC after giving what was later found to be flawed statistical evidence in the trial of Sally Clark, who was wrongfully convicted of killing her children.
A GMC fitness-to-practise panel found him guilty of serious professional misconduct and ordered that he be struck off the medical register. High Court judge Mr Justice Collins overruled the decision last month, saying that Professor Meadow had made an easy mistake in misinterpreting the statistics.
The GMC's findings against Professor Meadow had 'increased the reluctance of medical practitioners to involve themselves in court proceedings', said Mr Justice Collins, and he concluded that expert witnesses should be immune from disciplinary proceedings unless referred on by the trial judge.
It was hoped that such a ruling would encourage doctors to continue to act as expert witnesses.
Many GPs welcomed the High Court ruling, including Dr Ted Willis, a GP in Brigg, North Lincolnshire, who said that the GMC's verdict had 'supported and maintained the blame culture that it avows to be trying to eliminate' (GP, 3 March).
But the GMC feels the ruling will have far wider implications.
Finlay Scott, the GMC's chief executive, said it was not seeking to reinstate Professor Meadow's removal from the register, but that the appeal would primarily be about 'important points of law and how the judgment would prevent us from acting in the public interest when a doctor has fallen significantly below acceptable standards'.
He continued: 'We agree with Mr Justice Collins that there is a problem to be solved.
'It cannot be in the public's interest if doctors are deterred from giving evidence, honestly and truthfully, and within their competence.
'However, we do not believe that the solution lies in extending the principle of immunity.'
Mr Scott added that the ruling was not simply a medical issue, but could cause wider legal problems because it 'extended to all witnesses of fact'.
To demonstrate the range of consequence of the ruling, he cited the case of Paul Stretford, the agent of footballer Wayne Rooney. Following Professor Meadow's case, the Football Association has suspended two charges against Mr Stretford relating to evidence he gave in court.
The GMC will learn whether it can appeal against the ruling in two weeks.