San Diego Child Only Known Person In World With This Rare Form Of Disease
Thursday, March 5, 2020
Photo by Shalina Chatlani
When KPBS met the Omler family a few years ago, they were still searching for a diagnosis for their son Damian’s mysterious disease. San Diego scientists gave them an answer. And now, they confirm Damian is one of a kind.
A rare condition
At his home in Linda Vista, 11-year-old Damian Omler often slams his back against his wheelchair as he watches rock legends like Slash shredding a guitar on the TV.
Damian’s mom, Gracie Omler, said he loves to “rock out.”
"Do you want more, or are you all done? Where do you want to go?" she asked him.
Damian can’t walk. Sometimes he needs a feeding tube. And he gets help using the bathroom. But, his parents say, he also goes to school and has friends. While Damian can’t communicate, he’s always laughing.
"He loves being silly, silly noises, he’s your typical boy, he likes to throw things, play with his brother," Omler said.
Damian has a form of Congenital Disorders of Glycosylation, or CDG for short. It’s a type of extremely rare disease that causes the body’s cells to malfunction, because sugars aren’t properly attaching to proteins.
But there are more than 100 different forms of CDG, because different genetic abnormalities can lead to poor sugar-protein connections. So, father Donnie Omler said for years they didn’t have a specific diagnosis.
"They were calling it 'CDG X' because there was no subtype to it. So that was kind of uncertainty, it was kind of a downer for us, because we're like, how do we include ourselves in the CDG community," Omler said.
But when scientists at Sanford Burnham Prebys Medical Discovery Institute in La Jolla took on the case five years ago, they were able to find the mutation. Doctors searched for several years to find another patient with Damian’s same condition. But they couldn’t find one.
And after consulting with the National Institutes of Health, doctors are now saying Damian has a new type CDG. As far as they know, he’s the only person in the world with it.
Searching for a genetic clue
At his lab in La Jolla, genetics scientist Hudson Freeze points to one of numerous photos on a wall. They are pictures of children he’s worked with who have CDG and other conditions.
"That’s my sister, and she’s also disabled, so you know I kind of know what it’s like to go through all the struggles they have," said Freeze.
Freeze says his lab has worked hundreds of children with CDG over the last two decades.
"A lot of them will have intellectual disability, neuropathy, poor brain development. So many of the patients are unable to walk," he said.
Freeze started working with Damian five years ago, when UC San Diego doctors turned the case and Damian’s skin cells over to him.
What they found is an entirely new gene in a DNA sequence where CDG can develop. They’re calling this disease CDG-GET4, which refers to that mutated gene in Damian’s body that’s stopping proteins from being guided to the right place.
"They have helpers and chaperones along the way, and with Damien’s one of his chaperones was completely gone. That’s what he’s lacking right now," Freeze said.
Freeze said this discovery is significant because understanding which mutations lead to CDG can help scientists design more therapies to treat it.
"What it does is to open up a whole new pathway of thinking for people who said, 'well I never thought about possibilities in that group of genes,'" Freeze said.
And that could open doors for other CDG patients to also get treatment. In Damien’s case, Freeze said there is one drug that could potentially help him, but it has some uncomfortable side effects.
But he said the other benefit of finding these genetic mutations is that people can do more family planning, if they know the mutation hereditary. And of course, families can also get some sense of closure.
Finally, some answers
And back at the Omler family home, Damian’s father Donnie said knowing the type of genetic mutation has been so comforting.
"When we found that out it was kind of a perspective for us to find out how rare Damian actually is. That was breathtaking for us," he said.
He said special needs parents are often left with questions. And even with a diagnosis they still want to learn more.
"We tell everybody we take it one day at a time. That’s all you can do," Omler said.
In the meantime, they think it’s important for special needs parents to know they have a community of support.
And Freeze said he believes as Damian’s case gets more publicity, more patients like him will be discovered and could potentially get treated.
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