Bill Nye Shares Family's Ataxia Struggle: 'Every Time You Lose Your Balance, You Think This Is the End' (Exclusive)

The beloved 'Science Guy' says many of his family members suffer from a rare neurological disorder that their ancestors had in colonial times

• Beloved "Science Guy" Bill Nye is sharing his family's long struggle with the degenerative neurological condition Ataxia for International Ataxia Awareness Day on Sept. 25

• The disorder affects balance and "any fine motor movement," Nye explains, sharing that symptoms are often dismissed as "carelessness"

• Recent breakthroughs have identified the gene repeat behind Ataxia — and as Nye says, "studying it may lead to other discoveries related to genes at large"

Ataxia may not be as well known as other degenerative conditions, but as Bill Nye says, “If you’re in my family, you hear about it all the time.”

That’s because the progressive disorder runs in his family — dating back to an ancestor from the colonial era.

A neurological condition that starts in the cerebellum and causes trouble with coordinating movement, Ataxia manifests with physical symptoms, the beloved “Science Guy” explains.

“You have trouble keeping your balance, you have trouble snapping your fingers — any fine motor movement,” Nye, 68, tells PEOPLE. “The other really pronounced one that they all complain about is trouble swallowing.”

Because some of the early symptoms can be dismissed as clumsiness, Nye says, “You second-guess yourself all the time: Every time you lose your balance, you think, ‘Well, this is it, this is the beginning of the end, this beginning of this is how I'm gonna live from now on.’ ”

As he shares, “My father, 14 times a day, would say, ‘It's just carelessness’: Just carelessness when he'd fall down, when he dropped something, when you break a glass while washing it, have trouble steering a car. ‘Oh, it's just carelessness.’ ”

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“But actually,” he continued, “It was this incomplete connection between what he wanted to do and what his cerebellum or his brain enabled him to do,” Nye explains. “And this led to all kinds of difficulty in his life.”

But for Sept. 25’s International Ataxia Awareness Day, Nye shares, there have been breakthroughs in Ataxia research that may help not only stop the progression of the disease, but help identify it in others.

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“A year and a half ago the gene repeat that causes it has been identified,” Nye tells PEOPLE. “It's been elusive for decades.”

In that time, he learned, “I almost certainly will not get it. My gene, the length of my repeating sequence, is too short to cause it.”

The feelings, he shared, were “two separate and parallel feelings.”

“First of all: ‘Wow, I'm not gonna get it.’ The reason I can't snap my fingers is actually just me.”

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“The other thing is so-called survivor's guilt that I'm the third kid,” he said, sharing that both his sister and brother have symptoms of Ataxia.

His sister, he says, uses a wheelchair and “she spends a lot of time sitting down,” while “my brother's symptoms are clearly getting more and more pronounced as he's gotten older.”

“For some reason, the repeat [I have] isn't long enough to cause these symptoms. With that in mind, I felt as though I finally had something I could contribute to society with respect to this condition — that I could finally raise awareness,” Nye tells PEOPLE.

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“For people who have it, you don't need to go to the world's foremost authority to realize that you're falling down, you can't swallow, you can't pick things up, you can't pick up a paper clip,” he said that sharing his family’s Ataxia symptoms “are pretty mild compared to other people with other forms of Ataxia. These other ones are really extraordinary.”

And progress on Ataxia, he says, may help with other disorders.

“Feel free to donate to the National Ataxia Foundation and contribute to the research because it's another genetic disorder — and studying it may lead to other discoveries related to genes at large,” he says. “It's really an exciting time, scientifically.”

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