A BBC spokesperson said: “We are confident in our journalism.
“As Laura Saunders is a candidate standing for election, it is clearly in the public interest to report allegations made against her.”
The betting watchdog is also looking into Mr Lee – who is Ms Saunders’ husband – over an alleged bet relating to the timing of the 4 July election.
Labour and the Liberal Democrats have both called on the Conservatives to suspend Ms Saunders and Craig Williams as Conservative candidates over political bets.
Last week Mr Williams, who had been a parliamentary aide to Prime Minister Rishi Sunak, apologised and said he had made a “huge error of judgement” over betting on the date of the general election.
Mr Williams, the Conservative candidate for Montgomeryshire and Glyndwr, allegedly placed a £100 bet on a July election three days before Mr Sunak announced the date.
Mr Sunak’s announced 4 July as the date of the general election on 22 May, taking much of Westminster by surprise.
A Conservative Party spokesman told the BBC: “We have been contacted by the Gambling Commission about a small number of individuals.”
The party said it would not be proper to comment further until any process was finished.
If someone uses confidential information to gain an unfair advantage when betting, this could be a criminal offence under section 42 of the Gambling Act.
On Wednesday, it emerged that a police officer working as part of the prime minister’s close protection team had been arrested following an allegation of bets on the timing of the election.
The officer was initially suspended by the Metropolitan Police and then arrested on suspicion of misconduct in public office.
The individual has been bailed pending further inquiries.
The Met was contacted by the Gambling Commission last Friday. It informed the force that it was investigating alleged bets made by a police constable from the Met’s Royalty and Specialist Protection Command.
A spokesperson for the Gambling Commission said: “The Gambling Commission regulates gambling in the interests of consumers and the wider public.
“Currently the Commission is investigating the possibility of offences concerning the date of the election. This is an ongoing investigation, and the Commission cannot provide any further details at this time.
“We are not confirming or denying the identity of any individuals involved in this investigation.”