A female president in my lifetime would be fantastic: Melinda Gates

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With the world focusing on the U.S. elections, the debate about what makes a suitable leader has never been fiercer, but the co-chair of the world's largest private charitable foundation hopes that one day there'll be a woman in the White House.

"I think having an important role model is important for all boys and girls whether that's a man or a woman," Melinda Gates, co-chair of Bill & Melinda Gates Foundation, told CNBC's Tania Bryer.

"To me it needs to be — you need to have a man in that (presidential) position, and you eventually need to have a woman, whether it's in my lifetime that would be fantastic. I certainly want it to be in my daughter's lifetime, absolutely."

When asked whether she'd like to see Hillary Clinton become the U.S.' first female president, Gates said she always keeps her vote private.

"Bill (Gates) and I always keep private who we are voting for in elections, so I'll wait to see what the outcome is and cheer on the other end."

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Other public figures have also spoken out on who they'd like to see win the election, with many hoping for a female U.S. president as soon as 2016.

Speaking at 2016's World Economic Forum, musician, will.i.am told CNBC he would vote for "Hillary" this November; while Lena Dunham, Snoop Dogg and Katy Perry, have all shown their public support for the candidate.

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Gates' comments come on the back on her and her husband's annual letter, whereby she calls for the "burden" of unpaid work — which "falls heaviest on women in poor countries" — to be redistributed evenly worldwide.

"Unless things change, girls today will spend hundreds of thousands more hours than boys doing unpaid work simply because society assumes it's their responsibility," Melinda Gates said in 2016's annual letter, adding that assigning most unpaid work to women "harms everyone."

Trump and his view on vaccinations

With the foundation constantly trying to find new ways of tackling extreme poverty and improving healthcare; promoting the use of vaccines is crucial to Bill and Melinda Gates.

Melinda Gates and Bill Gates of the Gates Foundation.
Brian Ach | Getty Images Entertainment | Getty Images

While Gates didn't reveal who she'd vote for, she did say she was "concerned any time any leader speaks out" and says something that is "a misrepresentation of the facts," in reference to Republican candidate Donald Trump's views on the issue of whether vaccinations lead to autism in children.

In September 2015, Trump's views on autism's association to child vaccinations were called to question at a CNN GOP debate, with Trump suggesting a link remained, even though the belief has been widely discredited.

At the debate, Trump said autism had become an "epidemic" which had become "totally out of control." The billionaire backed up his comments, with a story of an employee's child who got diagnosed with the condition, after they got "a tremendous fever" and "very, very sick" due to a recently administered vaccine. Trump added however that he was in favor of vaccinations, but they should be given in "smaller doses" over a longer period of time.

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In response to Trump's comments, Gates said she wants to make sure this "myth" about vaccines is dismissed.

"Unfortunately autism got mixed up with vaccines for quite a long time and that myth existed in our society and I want to make sure it's not perpetuated."

"So I spoke out on that because I want people to know that's not the truth and in fact it's been completely debunked. The doctor who actually said that, his license has been pulled from him, and it's taken us a long time to come back from that myth."

"Bill and I are fundamental believers in vaccines because they save children's lives and that's true throughout the world."

To read more about Bill and Melinda Gates annual letter, click here.

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By CNBC's Alexandra Gibbs, follow her @AlexGibbsy and @CNBCi