The BBC has more than 400 transgender staff, a confidential internal survey has revealed.
The figure represents more than one in 50 of the workforce – about four times higher than the proportion in the population at large.
And it stunned the BBC executive behind the research, who described the total number of trans employees, at 417, as 'very, very high'.
Tunde Ogungbesan, the BBC's director of diversity, has now launched a major reform to make the Corporation more 'trans-friendly' following the findings.
The issue of trans rights has divided Britain, with a split between traditionalists who believe gender is assigned at birth and progressives who believe a liberal society should make strides against any form of discrimination towards trans people.
Tunde Ogungbesan (pictured), the BBC's director of diversity, has now launched a major reform to make the Corporation more 'trans-friendly' following the findings
Using personal information about BBC staff that 'only a couple of people would ever know', Mr Ogungbesan also revealed that 11 per cent of BBC employees were lesbian, gay, bisexual or transgender.
But he said he did not regard the BBC as diverse enough, claiming more lesbians were needed.
Of the Corporation's 21,239 staff, almost a quarter declined to reveal their orientation.
Of the remainder 2.2 per cent said they were bisexual, 4.8 per cent were gay men and 1.3 per cent lesbian.
The BBC's trans employees include local radio presenter Stephanie Hirst (pictured)
Of the whole UK, 2 per cent of people say they are lesbian, gay or bisexual, according to official figures from 2016.
The BBC's research comes as the Government prepares to announce plans to make it less stressful and bureaucratic for people to be able to change gender.
Equalities Minister Penny Mordaunt, who will launch a consultation on Tuesday, has told Cabinet colleagues she regards it as 'one of the most important issues facing modern British society'.
Mr Ogungbesan revealed his findings at a conference attended by senior civil servants, doctors and transgender rights campaigners earlier last month.
He teasingly told them: 'Can someone have a guess at how many people have disclosed they are transgender at the BBC. Ten? Anyone else? Twenty? Not bad. One more? I will put you out of your misery. We've got 417... almost two per cent. That is very, very high.'
Mr Ogungbesan told the Westminster Social Policy Forum that the results would lead to the rewriting of the BBC's 'style guide', which sets out the rules on 'fairness and terminology' at the corporation.
He added: 'What we are on is a journey within the BBC... if we can create a culture where everyone feels they can bring their best work into the organisation and with that you can begin to change from within the thought processes and the ways people behave and the way they broadcast their programmes, then we would have achieved what we are trying to do.'
The BBC has more than 400 transgender staff, a confidential internal survey has revealed
Last night, critics expressed fears that BBC producers could be forced to shoehorn politically- correct storylines about transgender people into programmes.
Nicola Williams, from feminist group Fair Play For Women – which objects to men being able to self-identify as women – said she was concerned about possible changes to the Corporation's output.