Sanfilippo gene therapy gained early support from affected families: NPR


Glenn (left to right), Beckham, Cara and Eliza O'Neill pose for a family photo in 2015. Eliza has Sanfilippo syndrome, a rare hereditary disorder.

Glenn (left to right), Beckham, Cara and Eliza O’Neill pose for a family photo in 2015. Eliza has Sanfilippo syndrome, a rare hereditary disorder.

Robert Clark


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Robert Clark

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When Eliza O’Neill was little, she was one of those kids who always needed to have an accessory, like a hat or a scarf.

“She would always go to the closet for my high heels and step into them — which scared us,” says her mother, Cara O’Neill, a pediatrician in Columbia, South Carolina.

But when Eliza turned 3, her parents noticed she was falling behind in her developmental milestones. She was diagnosed with pragmatic speech delay, meaning she had learned a lot of words, for example, but didn’t use them habitually in social situations.

In 2013, one of Cara’s colleagues suggested testing Eliza for a group of metabolic disorders, just to rule them out.

But the test came back positive for something called Sanfilippo syndrome.

Cara remembers learning about this rare hereditary disease in medical school.

“When they said the word, everything came rushing back,” she says. “And it was just this ball of terror, like, oh, my God, this is horrible.”

Children with Sanfilippo have a defective gene that prevents them from breaking down heparin sulfate, a molecule essential for normal cell function. As it accumulates in the body, it causes serious complications.

Children with Sanfilippo lose the ability to speak and walk. They have seizures and usually don’t make it past adolescence, depending on the Sanfilippo Healing Foundationthat the O’Neills started and continue to run.

For Eliza’s father, Glenn O’Neill, it took some time after learning of Eliza’s test results for the diagnosis to be made.

“It was only when I got home that I realized how quickly the degeneration had happened,” he says. “And that’s really when we said, ‘My God. Whatever we have to do, we have to do it now.'”

Finding treatment

At Nationwide Children’s Hospital in Columbus, Ohio, researcher Haiyan Fu had been working on gene therapy in mice for Sanfilippo since the late 1990s.

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