Claire Stern was never hard to find. Just follow the sound of squeaking sneakers and a bouncing basketball.

“I’ve been playing basketball since kindergarten,” Stern says. “It kind of becomes who you are and what you’re known for.”

For years, Stern’s future seemed as clear as the three-point line beneath her feet. Basketball led her to North Dakota State University, where she was a Division I athlete. But in June 2025, everything changed.

After experiencing several sudden seizure-like episodes in one night, Stern — just 19 years old at the time — was rushed to the hospital. There, doctors discovered that the seizures weren’t seizures at all; they were a series of small heart attacks. Weeks later, a genetic test revealed that Stern had an extremely rare DNA mutation that had slowly weakened her heart.

It’s known as PPA2 deficiency, and fewer than 20 people are known to have it worldwide. The mutation compromises energy production in heart cells and can cause heart failure and sudden cardiac arrest. 

Living with PPA2 deficiency means getting an implantable defibrillator, which Stern did. But beyond that, there is no treatment. 

Her doctor told her that for every year she continued playing basketball, she’d lose 10 years off of her life.

Her passion for hoops was replaced by a passion for helping others with rare genetic diseases. Alongside her mom, Sheila, Claire Stern created the RareDNA Foundation, which supports research that aims to illuminate what causes PPA2 deficiency and how it can be diagnosed sooner — and treated more effectively.

The RareDNA Foundation is fueling the work of Forum Kamdar, MD, PhD, a cardiologist and an associate professor of medicine at the University of Minnesota Medical School, who examines heart cells made from stem cells of people who have genetic disorders — including Stern — to better understand how these disorders function and to find treatments.

Stern says basketball taught her how to fight through adversity and pursue a goal bigger than herself. And while her time as a basketball player might be over, the lessons she learned remain.

“I started realizing life is bigger than basketball,” she says. “Basketball has been a huge part of my life, but now the RareDNA Foundation is a big part of my new purpose.”